15 puzzle solver: Difference between revisions
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=={{header|Phix}}== |
=={{header|Phix}}== |
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<lang Phix>-- |
<!--<lang Phix>--> |
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<span style="color: #000080;font-style:italic;">-- demo\rosetta\Solve15puzzle.exw</span> |
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constant STM = 0 -- single-tile metrics. |
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<span style="color: #008080;">constant</span> <span style="color: #000000;">STM</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span> <span style="color: #000080;font-style:italic;">-- single-tile metrics.</span> |
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constant MTM = 0 -- multi-tile metrics. |
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<span style="color: #008080;">constant</span> <span style="color: #000000;">MTM</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span> <span style="color: #000080;font-style:italic;">-- multi-tile metrics.</span> |
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if STM and MTM then ?9/0 end if -- both prohibited |
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<span style="color: #008080;">if</span> <span style="color: #000000;">STM</span> <span style="color: #008080;">and</span> <span style="color: #000000;">MTM</span> <span style="color: #008080;">then</span> <span style="color: #0000FF;">?<span style="color: #000000;">9<span style="color: #0000FF;">/<span style="color: #000000;">0</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #000080;font-style:italic;">-- both prohibited |
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-- 0 0 -- fastest, but non-optimal |
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-- |
-- 0 0 -- fastest, but non-optimal |
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-- |
-- 1 0 -- optimal in STM |
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-- 0 1 -- optimal in MTM (slowest by far) |
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--Note: The fast method uses an inadmissible heuristic - see "not STM" in iddfs(). |
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-- It explores mtm-style using the higher stm heuristic and may therefore |
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-- fail badly in some cases.</span> |
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<span style="color: #008080;">constant</span> <span style="color: #000000;">SIZE</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">4</span> |
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<span style="color: #008080;">constant</span> <span style="color: #000000;">goal</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span> <span style="color: #000000;">1<span style="color: #0000FF;">,</span> <span style="color: #000000;">2<span style="color: #0000FF;">,</span> <span style="color: #000000;">3<span style="color: #0000FF;">,</span> <span style="color: #000000;">4<span style="color: #0000FF;">,</span> |
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<span style="color: #000000;">5<span style="color: #0000FF;">,</span> <span style="color: #000000;">6<span style="color: #0000FF;">,</span> <span style="color: #000000;">7<span style="color: #0000FF;">,</span> <span style="color: #000000;">8<span style="color: #0000FF;">,</span> |
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<span style="color: #000000;">9<span style="color: #0000FF;">,<span style="color: #000000;">10<span style="color: #0000FF;">,<span style="color: #000000;">11<span style="color: #0000FF;">,<span style="color: #000000;">12<span style="color: #0000FF;">,</span> |
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<span style="color: #000000;">13<span style="color: #0000FF;">,<span style="color: #000000;">14<span style="color: #0000FF;">,<span style="color: #000000;">15<span style="color: #0000FF;">,</span> <span style="color: #000000;">0<span style="color: #0000FF;">}</span> |
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<span style="color: #000080;font-style:italic;">-- |
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-- multi-tile-metric walking distance heuristic lookup (mmwd). |
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-- ========================================================== |
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-- Uses patterns of counts of tiles in/from row/col, eg the solved state |
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-- (ie goal above) could be represented by the following: |
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-- {{4,0,0,0}, |
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-- {0,4,0,0}, |
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-- {0,0,4,0}, |
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-- {0,0,0,3}} |
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-- ie row/col 1 contains 4 tiles from col/row 1, etc. In this case |
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-- both are identical, but you can count row/col or col/row, and then |
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-- add them together. There are up to 24964 possible patterns. The |
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-- blank space is not counted. Note that a vertical move cannot change |
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-- a vertical pattern, ditto horizontal, and basic symmetry means that |
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-- row/col and col/row patterns will match (at least, that is, if they |
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-- are calculated sympathetically), halving the setup cost. |
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-- The data is just the number of moves made before this pattern was |
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-- first encountered, in a breadth-first search, backwards from the |
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-- goal state, until all patterns have been enumerated. |
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-- (The same ideas/vars are now also used for stm metrics when MTM=0) |
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--</span> |
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<span style="color: #004080;">sequence</span> <span style="color: #000000;">wdkey</span> <span style="color: #000080;font-style:italic;">-- one such 4x4 pattern</span> |
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<span style="color: #008080;">constant</span> <span style="color: #000000;">mmwd</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">new_dict<span style="color: #0000FF;">(<span style="color: #0000FF;">)</span> <span style="color: #000080;font-style:italic;">-- lookup table, data is walking distance. |
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-- |
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-- We use two to-do lists: todo is the current list, and everything |
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-- of walkingdistance+1 ends up on tdnx. Once todo is exhausted, we |
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-- swap the dictionary-ids, so tdnx automatically becomes empty. |
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-- Key is an mmwd pattern as above, and data is {distance,space_idx}. |
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--</span> |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">todo</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">new_dict<span style="color: #0000FF;">(<span style="color: #0000FF;">)</span> |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">tdnx</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">new_dict<span style="color: #0000FF;">(<span style="color: #0000FF;">)</span> |
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<span style="color: #000080;font-style:italic;">--</span> |
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<span style="color: #008080;">enum</span> <span style="color: #000000;">UP</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1<span style="color: #0000FF;">,</span> <span style="color: #000000;">DOWN</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">-<span style="color: #000000;">1</span> |
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<span style="color: #008080;">procedure</span> <span style="color: #000000;">explore<span style="color: #0000FF;">(<span style="color: #004080;">integer</span> <span style="color: #000000;">space_idx<span style="color: #0000FF;">,</span> <span style="color: #000000;">walking_distance<span style="color: #0000FF;">,</span> <span style="color: #000000;">direction<span style="color: #0000FF;">)</span> |
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<span style="color: #000080;font-style:italic;">-- |
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-- Given a space index, explore all the possible moves in direction, |
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-- setting the distance and extending the tdnx table. |
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--</span> |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">tile_idx</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">space_idx<span style="color: #0000FF;">+<span style="color: #000000;">direction</span> |
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<span style="color: #008080;">for</span> <span style="color: #000000;">group<span style="color: #0000FF;">=<span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">SIZE</span> <span style="color: #008080;">do</span> |
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<span style="color: #008080;">if</span> <span style="color: #000000;">wdkey<span style="color: #0000FF;">[<span style="color: #000000;">tile_idx<span style="color: #0000FF;">]<span style="color: #0000FF;">[<span style="color: #000000;">group<span style="color: #0000FF;">]</span> <span style="color: #008080;">then</span> |
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<span style="color: #000080;font-style:italic;">-- ie: check row tile_idx for tiles belonging to rows 1..4 |
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-- Swap one of those tiles with the space</span> |
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<span style="color: #000000;">wdkey<span style="color: #0000FF;">[<span style="color: #000000;">tile_idx<span style="color: #0000FF;">]<span style="color: #0000FF;">[<span style="color: #000000;">group<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">-=</span> <span style="color: #000000;">1</span> |
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<span style="color: #000000;">wdkey<span style="color: #0000FF;">[<span style="color: #000000;">space_idx<span style="color: #0000FF;">]<span style="color: #0000FF;">[<span style="color: #000000;">group<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span> |
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<span style="color: #008080;">if</span> <span style="color: #7060A8;">getd_index<span style="color: #0000FF;">(<span style="color: #000000;">wdkey<span style="color: #0000FF;">,<span style="color: #000000;">mmwd<span style="color: #0000FF;">)<span style="color: #0000FF;">=<span style="color: #000000;">0</span> <span style="color: #008080;">then</span> |
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<span style="color: #000080;font-style:italic;">-- save the walking distance value</span> |
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<span style="color: #7060A8;">setd<span style="color: #0000FF;">(<span style="color: #000000;">wdkey<span style="color: #0000FF;">,<span style="color: #000000;">walking_distance<span style="color: #0000FF;">+<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">mmwd<span style="color: #0000FF;">)</span> |
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<span style="color: #000080;font-style:italic;">-- and add to the todo next list:</span> |
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<span style="color: #008080;">if</span> <span style="color: #7060A8;">getd_index<span style="color: #0000FF;">(<span style="color: #000000;">wdkey<span style="color: #0000FF;">,<span style="color: #000000;">tdnx<span style="color: #0000FF;">)<span style="color: #0000FF;">!=<span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #0000FF;">?<span style="color: #000000;">9<span style="color: #0000FF;">/<span style="color: #000000;">0</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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<span style="color: #7060A8;">setd<span style="color: #0000FF;">(<span style="color: #000000;">wdkey<span style="color: #0000FF;">,<span style="color: #0000FF;">{<span style="color: #000000;">walking_distance<span style="color: #0000FF;">+<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">tile_idx<span style="color: #0000FF;">}<span style="color: #0000FF;">,<span style="color: #000000;">tdnx<span style="color: #0000FF;">)</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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<span style="color: #008080;">if</span> <span style="color: #000000;">MTM</span> <span style="color: #008080;">then</span> |
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<span style="color: #008080;">if</span> <span style="color: #000000;">tile_idx<span style="color: #0000FF;">><span style="color: #000000;">1</span> <span style="color: #008080;">and</span> <span style="color: #000000;">tile_idx<span style="color: #0000FF;"><<span style="color: #000000;">SIZE</span> <span style="color: #008080;">then</span> |
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<span style="color: #000080;font-style:italic;">-- mtm: same direction means same distance:</span> |
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<span style="color: #000000;">explore<span style="color: #0000FF;">(<span style="color: #000000;">tile_idx<span style="color: #0000FF;">,</span> <span style="color: #000000;">walking_distance<span style="color: #0000FF;">,</span> <span style="color: #000000;">direction<span style="color: #0000FF;">)</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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<span style="color: #000080;font-style:italic;">-- Revert the swap so we can look at the next candidate.</span> |
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<span style="color: #000000;">wdkey<span style="color: #0000FF;">[<span style="color: #000000;">tile_idx<span style="color: #0000FF;">]<span style="color: #0000FF;">[<span style="color: #000000;">group<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span> |
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<span style="color: #000000;">wdkey<span style="color: #0000FF;">[<span style="color: #000000;">space_idx<span style="color: #0000FF;">]<span style="color: #0000FF;">[<span style="color: #000000;">group<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">-=</span> <span style="color: #000000;">1</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> |
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<span style="color: #008080;">procedure</span> <span style="color: #000000;">generate_mmwd<span style="color: #0000FF;">(<span style="color: #0000FF;">)</span> |
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<span style="color: #000080;font-style:italic;">-- Perform a breadth-first search begining with the solved puzzle state |
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-- and exploring from there until no more new patterns emerge.</span> |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">walking_distance</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0<span style="color: #0000FF;">,</span> <span style="color: #000000;">space</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">4</span> |
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<span style="color: #000000;">wdkey</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{<span style="color: #0000FF;">{<span style="color: #000000;">4<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">}<span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- \</span> |
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<span style="color: #0000FF;">{<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">4<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">}<span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- } 4 tiles in correct row positions</span> |
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<span style="color: #0000FF;">{<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">4<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">}<span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- /</span> |
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<span style="color: #0000FF;">{<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">3<span style="color: #0000FF;">}<span style="color: #0000FF;">}</span> <span style="color: #000080;font-style:italic;">-- 3 tiles in correct row position</span> |
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<span style="color: #7060A8;">setd<span style="color: #0000FF;">(<span style="color: #000000;">wdkey<span style="color: #0000FF;">,<span style="color: #000000;">walking_distance<span style="color: #0000FF;">,<span style="color: #000000;">mmwd<span style="color: #0000FF;">)</span> |
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<span style="color: #008080;">while</span> <span style="color: #000000;">1</span> <span style="color: #008080;">do</span> |
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<span style="color: #008080;">if</span> <span style="color: #000000;">space<span style="color: #0000FF;"><<span style="color: #000000;">4</span> <span style="color: #008080;">then</span> <span style="color: #000000;">explore<span style="color: #0000FF;">(<span style="color: #000000;">space<span style="color: #0000FF;">,</span> <span style="color: #000000;">walking_distance<span style="color: #0000FF;">,</span> <span style="color: #000000;">UP<span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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<span style="color: #008080;">if</span> <span style="color: #000000;">space<span style="color: #0000FF;">><span style="color: #000000;">1</span> <span style="color: #008080;">then</span> <span style="color: #000000;">explore<span style="color: #0000FF;">(<span style="color: #000000;">space<span style="color: #0000FF;">,</span> <span style="color: #000000;">walking_distance<span style="color: #0000FF;">,</span> <span style="color: #000000;">DOWN<span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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<span style="color: #008080;">if</span> <span style="color: #7060A8;">dict_size<span style="color: #0000FF;">(<span style="color: #000000;">todo<span style="color: #0000FF;">)<span style="color: #0000FF;">=<span style="color: #000000;">0</span> <span style="color: #008080;">then</span> |
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<span style="color: #008080;">if</span> <span style="color: #7060A8;">dict_size<span style="color: #0000FF;">(<span style="color: #000000;">tdnx<span style="color: #0000FF;">)<span style="color: #0000FF;">=<span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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<span style="color: #0000FF;">{<span style="color: #000000;">todo<span style="color: #0000FF;">,<span style="color: #000000;">tdnx<span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{<span style="color: #000000;">tdnx<span style="color: #0000FF;">,<span style="color: #000000;">todo<span style="color: #0000FF;">}</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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<span style="color: #000000;">wdkey</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">getd_partial_key<span style="color: #0000FF;">(<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">todo<span style="color: #0000FF;">)</span> |
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<span style="color: #0000FF;">{<span style="color: #000000;">walking_distance<span style="color: #0000FF;">,<span style="color: #000000;">space<span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">getd<span style="color: #0000FF;">(<span style="color: #000000;">wdkey<span style="color: #0000FF;">,<span style="color: #000000;">todo<span style="color: #0000FF;">)</span> |
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<span style="color: #7060A8;">deld<span style="color: #0000FF;">(<span style="color: #000000;">wdkey<span style="color: #0000FF;">,<span style="color: #000000;">todo<span style="color: #0000FF;">)</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">while</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> |
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<span style="color: #008080;">function</span> <span style="color: #000000;">walking_distance<span style="color: #0000FF;">(<span style="color: #004080;">sequence</span> <span style="color: #000000;">puzzle<span style="color: #0000FF;">)</span> |
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<span style="color: #004080;">sequence</span> <span style="color: #000000;">rkey</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat<span style="color: #0000FF;">(<span style="color: #7060A8;">repeat<span style="color: #0000FF;">(<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">SIZE<span style="color: #0000FF;">)<span style="color: #0000FF;">,<span style="color: #000000;">SIZE<span style="color: #0000FF;">)<span style="color: #0000FF;">,</span> |
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<span style="color: #000000;">ckey</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat<span style="color: #0000FF;">(<span style="color: #7060A8;">repeat<span style="color: #0000FF;">(<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">SIZE<span style="color: #0000FF;">)<span style="color: #0000FF;">,<span style="color: #000000;">SIZE<span style="color: #0000FF;">)</span> |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">k</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span> |
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<span style="color: #008080;">for</span> <span style="color: #000000;">i<span style="color: #0000FF;">=<span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">SIZE</span> <span style="color: #008080;">do</span> <span style="color: #000080;font-style:italic;">-- rows</span> |
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<span style="color: #008080;">for</span> <span style="color: #000000;">j<span style="color: #0000FF;">=<span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">SIZE</span> <span style="color: #008080;">do</span> <span style="color: #000080;font-style:italic;">-- columns</span> |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">tile</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">puzzle<span style="color: #0000FF;">[<span style="color: #000000;">k<span style="color: #0000FF;">]</span> |
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<span style="color: #008080;">if</span> <span style="color: #000000;">tile<span style="color: #0000FF;">!=<span style="color: #000000;">0</span> <span style="color: #008080;">then</span> |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">row</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">floor<span style="color: #0000FF;">(<span style="color: #0000FF;">(<span style="color: #000000;">tile<span style="color: #0000FF;">-<span style="color: #000000;">1<span style="color: #0000FF;">)<span style="color: #0000FF;">/<span style="color: #000000;">4<span style="color: #0000FF;">)<span style="color: #0000FF;">+<span style="color: #000000;">1<span style="color: #0000FF;">,</span> |
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<span style="color: #000000;">col</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mod<span style="color: #0000FF;">(<span style="color: #000000;">tile<span style="color: #0000FF;">-<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">4<span style="color: #0000FF;">)<span style="color: #0000FF;">+<span style="color: #000000;">1</span> |
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<span style="color: #000000;">rkey<span style="color: #0000FF;">[<span style="color: #000000;">i<span style="color: #0000FF;">]<span style="color: #0000FF;">[<span style="color: #000000;">row<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span> |
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<span style="color: #000000;">ckey<span style="color: #0000FF;">[<span style="color: #000000;">j<span style="color: #0000FF;">]<span style="color: #0000FF;">[<span style="color: #000000;">col<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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<span style="color: #000000;">k</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span> |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
|||
<span style="color: #008080;">if</span> <span style="color: #7060A8;">getd_index<span style="color: #0000FF;">(<span style="color: #000000;">rkey<span style="color: #0000FF;">,<span style="color: #000000;">mmwd<span style="color: #0000FF;">)<span style="color: #0000FF;">=<span style="color: #000000;">0</span> |
|||
<span style="color: #008080;">or</span> <span style="color: #7060A8;">getd_index<span style="color: #0000FF;">(<span style="color: #000000;">ckey<span style="color: #0000FF;">,<span style="color: #000000;">mmwd<span style="color: #0000FF;">)<span style="color: #0000FF;">=<span style="color: #000000;">0</span> <span style="color: #008080;">then</span> |
|||
<span style="color: #0000FF;">?<span style="color: #000000;">9<span style="color: #0000FF;">/<span style="color: #000000;">0</span> <span style="color: #000080;font-style:italic;">-- sanity check</span> |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
|||
<span style="color: #004080;">integer</span> <span style="color: #000000;">rwd</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">getd<span style="color: #0000FF;">(<span style="color: #000000;">rkey<span style="color: #0000FF;">,<span style="color: #000000;">mmwd<span style="color: #0000FF;">)<span style="color: #0000FF;">,</span> |
|||
<span style="color: #000000;">cwd</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">getd<span style="color: #0000FF;">(<span style="color: #000000;">ckey<span style="color: #0000FF;">,<span style="color: #000000;">mmwd<span style="color: #0000FF;">)</span> |
|||
<span style="color: #008080;">return</span> <span style="color: #000000;">rwd<span style="color: #0000FF;">+<span style="color: #000000;">cwd</span> |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span> |
|||
<span style="color: #004080;">sequence</span> <span style="color: #000000;">puzzle</span> |
|||
<span style="color: #004080;">string</span> <span style="color: #000000;">res</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">""</span> |
|||
<span style="color: #004080;">atom</span> <span style="color: #000000;">t0</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">time<span style="color: #0000FF;">(<span style="color: #0000FF;">)<span style="color: #0000FF;">,</span> |
|||
<span style="color: #000000;">t1</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">time<span style="color: #0000FF;">(<span style="color: #0000FF;">)<span style="color: #0000FF;">+<span style="color: #000000;">1</span> |
|||
<span style="color: #004080;">atom</span> <span style="color: #000000;">tries</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span> |
|||
<span style="color: #008080;">constant</span> <span style="color: #000000;">ok</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{<span style="color: #0000FF;">{<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">}<span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- left</span> |
|||
<span style="color: #0000FF;">{<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">}<span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- up</span> |
|||
<span style="color: #0000FF;">{<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">}<span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- down</span> |
|||
<span style="color: #0000FF;">{<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">0<span style="color: #0000FF;">}<span style="color: #0000FF;">}</span> <span style="color: #000080;font-style:italic;">-- right |
|||
<!--</lang>--> |
|||
<!--<lang Phix>--> |
|||
--Note: The fast method uses an inadmissible heuristic - see "not STM" in iddfs(). |
|||
<span style="color: #008080;">function</span> <span style="color: #000000;">iddfs<span style="color: #0000FF;">(<span style="color: #004080;">integer</span> <span style="color: #000000;">step<span style="color: #0000FF;">,</span> <span style="color: #000000;">lim<span style="color: #0000FF;">,</span> <span style="color: #000000;">space<span style="color: #0000FF;">,</span> <span style="color: #000000;">prevmv<span style="color: #0000FF;">)</span> |
|||
-- It explores mtm-style using the higher stm heuristic and may therefore |
|||
<span style="color: #008080;">if</span> <span style="color: #7060A8;">time<span style="color: #0000FF;">(<span style="color: #0000FF;">)<span style="color: #0000FF;">><span style="color: #000000;">t1</span> <span style="color: #008080;">then</span> |
|||
-- fail badly in some cases. |
|||
<span style="color: #7060A8;">printf<span style="color: #0000FF;">(<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #008000;">"working... (depth=%d, tries=%d, time=%3ds)\r"<span style="color: #0000FF;">,<span style="color: #0000FF;">{<span style="color: #000000;">lim<span style="color: #0000FF;">,<span style="color: #000000;">tries<span style="color: #0000FF;">,<span style="color: #7060A8;">time<span style="color: #0000FF;">(<span style="color: #0000FF;">)<span style="color: #0000FF;">-<span style="color: #000000;">t0<span style="color: #0000FF;">}<span style="color: #0000FF;">)</span> |
|||
<span style="color: #000000;">t1</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">time<span style="color: #0000FF;">(<span style="color: #0000FF;">)<span style="color: #0000FF;">+<span style="color: #000000;">1</span> |
|||
constant SIZE = 4 |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
|||
<span style="color: #000000;">tries</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span> |
|||
constant goal = { 1, 2, 3, 4, |
|||
<span style="color: #004080;">integer</span> <span style="color: #000000;">d</span> <span style="color: #0000FF;">=</span> <span style="color: #008080;">iff<span style="color: #0000FF;">(<span style="color: #000000;">step<span style="color: #0000FF;">==<span style="color: #000000;">lim<span style="color: #0000FF;">?<span style="color: #000000;">0<span style="color: #0000FF;">:<span style="color: #000000;">walking_distance<span style="color: #0000FF;">(<span style="color: #000000;">puzzle<span style="color: #0000FF;">)<span style="color: #0000FF;">)</span> |
|||
5, 6, 7, 8, |
|||
<span style="color: #008080;">if</span> <span style="color: #000000;">d<span style="color: #0000FF;">=<span style="color: #000000;">0</span> <span style="color: #008080;">then</span> |
|||
9,10,11,12, |
|||
13,14,15, 0} |
|||
<span style="color: #008080;">return</span> <span style="color: #0000FF;">(<span style="color: #000000;">puzzle<span style="color: #0000FF;">==<span style="color: #000000;">goal<span style="color: #0000FF;">)</span> |
|||
-- |
|||
<span style="color: #008080;">elsif</span> <span style="color: #000000;">step<span style="color: #0000FF;">+<span style="color: #000000;">d<span style="color: #0000FF;"><=<span style="color: #000000;">lim</span> <span style="color: #008080;">then</span> |
|||
-- multi-tile-metric walking distance heuristic lookup (mmwd). |
|||
-- ========================================================== |
|||
<span style="color: #008080;">for</span> <span style="color: #000000;">mv<span style="color: #0000FF;">=<span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">4</span> <span style="color: #008080;">do</span> <span style="color: #000080;font-style:italic;">-- l/u/d/r</span> |
|||
-- Uses patterns of counts of tiles in/from row/col, eg the solved state |
|||
<span style="color: #008080;">if</span> <span style="color: #000000;">prevmv<span style="color: #0000FF;">!=<span style="color: #0000FF;">(<span style="color: #000000;">5<span style="color: #0000FF;">-<span style="color: #000000;">mv<span style="color: #0000FF;">)</span> <span style="color: #000080;font-style:italic;">-- not l after r or vice versa, ditto u/d</span> |
|||
-- (ie goal above) could be represented by the following: |
|||
<span style="color: #008080;">and</span> <span style="color: #000000;">ok<span style="color: #0000FF;">[<span style="color: #000000;">mv<span style="color: #0000FF;">]<span style="color: #0000FF;">[<span style="color: #000000;">space<span style="color: #0000FF;">]</span> <span style="color: #008080;">then</span> |
|||
-- {{4,0,0,0}, |
|||
<span style="color: #004080;">integer</span> <span style="color: #000000;">nspace</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">space<span style="color: #0000FF;">+<span style="color: #0000FF;">{<span style="color: #0000FF;">-<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #0000FF;">-<span style="color: #000000;">4<span style="color: #0000FF;">,<span style="color: #0000FF;">+<span style="color: #000000;">4<span style="color: #0000FF;">,<span style="color: #0000FF;">+<span style="color: #000000;">1<span style="color: #0000FF;">}<span style="color: #0000FF;">[<span style="color: #000000;">mv<span style="color: #0000FF;">]</span> |
|||
-- {0,4,0,0}, |
|||
<span style="color: #004080;">integer</span> <span style="color: #000000;">tile</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">puzzle<span style="color: #0000FF;">[<span style="color: #000000;">nspace<span style="color: #0000FF;">]</span> |
|||
-- {0,0,4,0}, |
|||
<span style="color: #008080;">if</span> <span style="color: #000000;">puzzle<span style="color: #0000FF;">[<span style="color: #000000;">space<span style="color: #0000FF;">]<span style="color: #0000FF;">!=<span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #0000FF;">?<span style="color: #000000;">9<span style="color: #0000FF;">/<span style="color: #000000;">0</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #000080;font-style:italic;">-- sanity check </span> |
|||
-- {0,0,0,3}} |
|||
<span style="color: #000000;">puzzle<span style="color: #0000FF;">[<span style="color: #000000;">space<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">tile</span> |
|||
-- ie row/col 1 contains 4 tiles from col/row 1, etc. In this case |
|||
<span style="color: #000000;">puzzle<span style="color: #0000FF;">[<span style="color: #000000;">nspace<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span> |
|||
-- both are identical, but you can count row/col or col/row, and then |
|||
<span style="color: #008080;">if</span> <span style="color: #000000;">iddfs<span style="color: #0000FF;">(<span style="color: #000000;">step<span style="color: #0000FF;">+<span style="color: #008080;">iff<span style="color: #0000FF;">(<span style="color: #000000;">MTM</span> <span style="color: #008080;">or</span> <span style="color: #008080;">not</span> <span style="color: #000000;">STM<span style="color: #0000FF;">?<span style="color: #0000FF;">(<span style="color: #000000;">prevmv<span style="color: #0000FF;">!=<span style="color: #000000;">mv<span style="color: #0000FF;">)<span style="color: #0000FF;">:<span style="color: #000000;">1<span style="color: #0000FF;">)<span style="color: #0000FF;">,<span style="color: #000000;">lim<span style="color: #0000FF;">,<span style="color: #000000;">nspace<span style="color: #0000FF;">,<span style="color: #000000;">mv<span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span> |
|||
-- add them together. There are up to 24964 possible patterns. The |
|||
<span style="color: #000000;">res</span> <span style="color: #0000FF;">&=</span> <span style="color: #008000;">"ludr"<span style="color: #0000FF;">[<span style="color: #000000;">mv<span style="color: #0000FF;">]</span> |
|||
-- blank space is not counted. Note that a vertical move cannot change |
|||
<span style="color: #008080;">return</span> <span style="color: #004600;">true</span> |
|||
-- a vertical pattern, ditto horizontal, and basic symmetry means that |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
|||
-- row/col and col/row patterns will match (at least, that is, if they |
|||
<span style="color: #000000;">puzzle<span style="color: #0000FF;">[<span style="color: #000000;">nspace<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">tile</span> |
|||
-- are calculated sympathetically), halving the setup cost. |
|||
<span style="color: #000000;">puzzle<span style="color: #0000FF;">[<span style="color: #000000;">space<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span> |
|||
-- The data is just the number of moves made before this pattern was |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
|||
-- first encountered, in a breadth-first search, backwards from the |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
|||
-- goal state, until all patterns have been enumerated. |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
|||
-- (The same ideas/vars are now also used for stm metrics when MTM=0) |
|||
<span style="color: #008080;">return</span> <span style="color: #004600;">false</span> |
|||
-- |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span> |
|||
sequence wdkey -- one such 4x4 pattern |
|||
constant mmwd = new_dict() -- lookup table, data is walking distance. |
|||
<span style="color: #008080;">function</span> <span style="color: #000000;">pack<span style="color: #0000FF;">(<span style="color: #004080;">string</span> <span style="color: #000000;">s<span style="color: #0000FF;">)</span> |
|||
<span style="color: #004080;">integer</span> <span style="color: #000000;">n</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length<span style="color: #0000FF;">(<span style="color: #000000;">s<span style="color: #0000FF;">)<span style="color: #0000FF;">,</span> <span style="color: #000000;">n0</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">n</span> |
|||
<span style="color: #008080;">for</span> <span style="color: #000000;">i<span style="color: #0000FF;">=<span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">4</span> <span style="color: #008080;">do</span> |
|||
-- |
|||
<span style="color: #004080;">integer</span> <span style="color: #000000;">ch</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"lrud"<span style="color: #0000FF;">[<span style="color: #000000;">i<span style="color: #0000FF;">]<span style="color: #0000FF;">,</span> <span style="color: #000000;">k</span> |
|||
-- We use two to-do lists: todo is the current list, and everything |
|||
<span style="color: #008080;">while</span> <span style="color: #000000;">1</span> <span style="color: #008080;">do</span> |
|||
-- of walkingdistance+1 ends up on tdnx. Once todo is exhausted, we |
|||
<span style="color: #000000;">k</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">match<span style="color: #0000FF;">(<span style="color: #7060A8;">repeat<span style="color: #0000FF;">(<span style="color: #000000;">ch<span style="color: #0000FF;">,<span style="color: #000000;">3<span style="color: #0000FF;">)<span style="color: #0000FF;">,<span style="color: #000000;">s<span style="color: #0000FF;">)</span> |
|||
-- swap the dictionary-ids, so tdnx automatically becomes empty. |
|||
<span style="color: #008080;">if</span> <span style="color: #000000;">k<span style="color: #0000FF;">=<span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
|||
-- Key is an mmwd pattern as above, and data is {distance,space_idx}. |
|||
<span style="color: #000000;">s<span style="color: #0000FF;">[<span style="color: #000000;">k<span style="color: #0000FF;">+<span style="color: #000000;">1<span style="color: #0000FF;">..<span style="color: #000000;">k<span style="color: #0000FF;">+<span style="color: #000000;">2<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"3"</span> |
|||
-- |
|||
<span style="color: #000000;">n</span> <span style="color: #0000FF;">-=</span> <span style="color: #000000;">2</span> |
|||
integer todo = new_dict() |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">while</span> |
|||
integer tdnx = new_dict() |
|||
<span style="color: #008080;">while</span> <span style="color: #000000;">1</span> <span style="color: #008080;">do</span> |
|||
<span style="color: #000000;">k</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">match<span style="color: #0000FF;">(<span style="color: #7060A8;">repeat<span style="color: #0000FF;">(<span style="color: #000000;">ch<span style="color: #0000FF;">,<span style="color: #000000;">2<span style="color: #0000FF;">)<span style="color: #0000FF;">,<span style="color: #000000;">s<span style="color: #0000FF;">)</span> |
|||
-- |
|||
<span style="color: #008080;">if</span> <span style="color: #000000;">k<span style="color: #0000FF;">=<span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
|||
<span style="color: #000000;">s<span style="color: #0000FF;">[<span style="color: #000000;">k<span style="color: #0000FF;">+<span style="color: #000000;">1<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">'2'</span> |
|||
enum UP = 1, DOWN = -1 |
|||
<span style="color: #000000;">n</span> <span style="color: #0000FF;">-=</span> <span style="color: #000000;">1</span> |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">while</span> |
|||
procedure explore(integer space_idx, walking_distance, direction) |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
|||
-- |
|||
<span style="color: #008080;">return</span> <span style="color: #0000FF;">{<span style="color: #000000;">n<span style="color: #0000FF;">,<span style="color: #008080;">iff<span style="color: #0000FF;">(<span style="color: #000000;">MTM<span style="color: #0000FF;">?<span style="color: #7060A8;">sprintf<span style="color: #0000FF;">(<span style="color: #008000;">"%d"<span style="color: #0000FF;">,<span style="color: #000000;">n<span style="color: #0000FF;">)<span style="color: #0000FF;">:<span style="color: #7060A8;">sprintf<span style="color: #0000FF;">(<span style="color: #008000;">"%d(%d)"<span style="color: #0000FF;">,<span style="color: #0000FF;">{<span style="color: #000000;">n<span style="color: #0000FF;">,<span style="color: #000000;">n0<span style="color: #0000FF;">}<span style="color: #0000FF;">)<span style="color: #0000FF;">)<span style="color: #0000FF;">,<span style="color: #000000;">s<span style="color: #0000FF;">}</span> |
|||
-- Given a space index, explore all the possible moves in direction, |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span> |
|||
-- setting the distance and extending the tdnx table. |
|||
-- |
|||
<span style="color: #008080;">procedure</span> <span style="color: #000000;">apply_moves<span style="color: #0000FF;">(<span style="color: #004080;">string</span> <span style="color: #000000;">moves<span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">space<span style="color: #0000FF;">)</span> |
|||
integer tile_idx = space_idx+direction |
|||
<span style="color: #004080;">integer</span> <span style="color: #000000;">move<span style="color: #0000FF;">,</span> <span style="color: #000000;">ch<span style="color: #0000FF;">,</span> <span style="color: #000000;">nspace</span> |
|||
for group=1 to SIZE do |
|||
<span style="color: #000000;">puzzle<span style="color: #0000FF;">[<span style="color: #000000;">space<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span> |
|||
if wdkey[tile_idx][group] then |
|||
<span style="color: #008080;">for</span> <span style="color: #000000;">i<span style="color: #0000FF;">=<span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length<span style="color: #0000FF;">(<span style="color: #000000;">moves<span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span> |
|||
-- ie: check row tile_idx for tiles belonging to rows 1..4 |
|||
<span style="color: #000000;">ch</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">moves<span style="color: #0000FF;">[<span style="color: #000000;">i<span style="color: #0000FF;">]</span> |
|||
-- Swap one of those tiles with the space |
|||
<span style="color: #008080;">if</span> <span style="color: #000000;">ch<span style="color: #0000FF;">><span style="color: #008000;">'3'</span> <span style="color: #008080;">then</span> |
|||
wdkey[tile_idx][group] -= 1 |
|||
<span style="color: #000000;">move</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">find<span style="color: #0000FF;">(<span style="color: #000000;">ch<span style="color: #0000FF;">,<span style="color: #008000;">"ulrd"<span style="color: #0000FF;">)</span> |
|||
wdkey[space_idx][group] += 1 |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
|||
<span style="color: #000080;font-style:italic;">-- (hint: "r" -> the 'r' does 1 |
|||
if getd_index(wdkey,mmwd)=0 then |
|||
- |
-- "r2" -> the 'r' does 1, the '2' does 1 |
||
-- "r3" -> the 'r' does 1, the '3' does 2!)</span> |
|||
<span style="color: #008080;">for</span> <span style="color: #000000;">j<span style="color: #0000FF;">=<span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">1<span style="color: #0000FF;">+<span style="color: #0000FF;">(<span style="color: #000000;">ch<span style="color: #0000FF;">=<span style="color: #008000;">'3'<span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span> |
|||
-- and add to the todo next list: |
|||
<span style="color: #000000;">nspace</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">space<span style="color: #0000FF;">+<span style="color: #0000FF;">{<span style="color: #0000FF;">-<span style="color: #000000;">4<span style="color: #0000FF;">,<span style="color: #0000FF;">-<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #0000FF;">+<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #000000;">4<span style="color: #0000FF;">}<span style="color: #0000FF;">[<span style="color: #000000;">move<span style="color: #0000FF;">]</span> |
|||
if getd_index(wdkey,tdnx)!=0 then ?9/0 end if |
|||
<span style="color: #000000;">puzzle<span style="color: #0000FF;">[<span style="color: #000000;">space<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">puzzle<span style="color: #0000FF;">[<span style="color: #000000;">nspace<span style="color: #0000FF;">]</span> |
|||
setd(wdkey,{walking_distance+1,tile_idx},tdnx) |
|||
<span style="color: #000000;">space</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">nspace</span> |
|||
end if |
|||
<span style="color: #000000;">puzzle<span style="color: #0000FF;">[<span style="color: #000000;">nspace<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span> |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
|||
if MTM then |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
|||
if tile_idx>1 and tile_idx<SIZE then |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> |
|||
-- mtm: same direction means same distance: |
|||
explore(tile_idx, walking_distance, direction) |
|||
<span style="color: #008080;">function</span> <span style="color: #000000;">solvable<span style="color: #0000FF;">(<span style="color: #004080;">sequence</span> <span style="color: #000000;">board<span style="color: #0000FF;">)</span> |
|||
end if |
|||
<span style="color: #004080;">integer</span> <span style="color: #000000;">n</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length<span style="color: #0000FF;">(<span style="color: #000000;">board<span style="color: #0000FF;">)</span> |
|||
end if |
|||
<span style="color: #004080;">sequence</span> <span style="color: #000000;">positions</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat<span style="color: #0000FF;">(<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">n<span style="color: #0000FF;">)</span> |
|||
<span style="color: #000080;font-style:italic;">-- prepare the mapping from each tile to its position</span> |
|||
-- Revert the swap so we can look at the next candidate. |
|||
<span style="color: #000000;">board<span style="color: #0000FF;">[<span style="color: #7060A8;">find<span style="color: #0000FF;">(<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">board<span style="color: #0000FF;">)<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">n</span> |
|||
wdkey[tile_idx][group] += 1 |
|||
<span style="color: #008080;">for</span> <span style="color: #000000;">i<span style="color: #0000FF;">=<span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">n</span> <span style="color: #008080;">do</span> |
|||
wdkey[space_idx][group] -= 1 |
|||
<span style="color: #000000;">positions<span style="color: #0000FF;">[<span style="color: #000000;">board<span style="color: #0000FF;">[<span style="color: #000000;">i<span style="color: #0000FF;">]<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">i</span> |
|||
end if |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
|||
end for |
|||
end procedure |
|||
<span style="color: #000080;font-style:italic;">-- check whether this is an even or odd state</span> |
|||
<span style="color: #004080;">integer</span> <span style="color: #000000;">row</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">floor<span style="color: #0000FF;">(<span style="color: #0000FF;">(<span style="color: #000000;">positions<span style="color: #0000FF;">[<span style="color: #000000;">16<span style="color: #0000FF;">]<span style="color: #0000FF;">-<span style="color: #000000;">1<span style="color: #0000FF;">)<span style="color: #0000FF;">/<span style="color: #000000;">4<span style="color: #0000FF;">)<span style="color: #0000FF;">,</span> |
|||
procedure generate_mmwd() |
|||
<span style="color: #000000;">col</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">(<span style="color: #000000;">positions<span style="color: #0000FF;">[<span style="color: #000000;">16<span style="color: #0000FF;">]<span style="color: #0000FF;">-<span style="color: #000000;">1<span style="color: #0000FF;">)<span style="color: #0000FF;">-<span style="color: #000000;">row<span style="color: #0000FF;">*<span style="color: #000000;">4</span> |
|||
-- Perform a breadth-first search begining with the solved puzzle state |
|||
<span style="color: #004080;">bool</span> <span style="color: #000000;">even_state</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">(<span style="color: #000000;">positions<span style="color: #0000FF;">[<span style="color: #000000;">16<span style="color: #0000FF;">]<span style="color: #0000FF;">==<span style="color: #000000;">16<span style="color: #0000FF;">)</span> <span style="color: #008080;">or</span> <span style="color: #0000FF;">(<span style="color: #7060A8;">mod<span style="color: #0000FF;">(<span style="color: #000000;">row<span style="color: #0000FF;">,<span style="color: #000000;">2<span style="color: #0000FF;">)<span style="color: #0000FF;">==<span style="color: #7060A8;">mod<span style="color: #0000FF;">(<span style="color: #000000;">col<span style="color: #0000FF;">,<span style="color: #000000;">2<span style="color: #0000FF;">)<span style="color: #0000FF;">)</span> |
|||
-- and exploring from there until no more new patterns emerge. |
|||
integer walking_distance = 0, space = 4 |
|||
<span style="color: #000080;font-style:italic;">-- count the even cycles</span> |
|||
<span style="color: #004080;">integer</span> <span style="color: #000000;">even_count</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span> |
|||
wdkey = {{4,0,0,0}, -- \ |
|||
<span style="color: #004080;">sequence</span> <span style="color: #000000;">visited</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat<span style="color: #0000FF;">(<span style="color: #004600;">false<span style="color: #0000FF;">,<span style="color: #000000;">16<span style="color: #0000FF;">)</span> |
|||
{0,4,0,0}, -- } 4 tiles in correct row positions |
|||
<span style="color: #008080;">for</span> <span style="color: #000000;">i<span style="color: #0000FF;">=<span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">n</span> <span style="color: #008080;">do</span> |
|||
{0,0,4,0}, -- / |
|||
<span style="color: #008080;">if</span> <span style="color: #008080;">not</span> <span style="color: #000000;">visited<span style="color: #0000FF;">[<span style="color: #000000;">i<span style="color: #0000FF;">]</span> <span style="color: #008080;">then</span> |
|||
{0,0,0,3}} -- 3 tiles in correct row position |
|||
<span style="color: #000080;font-style:italic;">-- a new cycle starts at i. Count its length..</span> |
|||
setd(wdkey,walking_distance,mmwd) |
|||
<span style="color: #004080;">integer</span> <span style="color: #000000;">cycle_length</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0<span style="color: #0000FF;">,</span> |
|||
while 1 do |
|||
<span style="color: #000000;">next_tile</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">i</span> |
|||
if space<4 then explore(space, walking_distance, UP) end if |
|||
<span style="color: #008080;">while</span> <span style="color: #008080;">not</span> <span style="color: #000000;">visited<span style="color: #0000FF;">[<span style="color: #000000;">next_tile<span style="color: #0000FF;">]</span> <span style="color: #008080;">do</span> |
|||
if space>1 then explore(space, walking_distance, DOWN) end if |
|||
<span style="color: #000000;">cycle_length</span> <span style="color: #0000FF;">+=<span style="color: #000000;">1</span> |
|||
if dict_size(todo)=0 then |
|||
<span style="color: #000000;">visited<span style="color: #0000FF;">[<span style="color: #000000;">next_tile<span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #004600;">true</span> |
|||
if dict_size(tdnx)=0 then exit end if |
|||
<span style="color: #000000;">next_tile</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">positions<span style="color: #0000FF;">[<span style="color: #000000;">next_tile<span style="color: #0000FF;">]</span> |
|||
{todo,tdnx} = {tdnx,todo} |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">while</span> |
|||
end if |
|||
<span style="color: #000000;">even_count</span> <span style="color: #0000FF;">+=</span> <span style="color: #0000FF;">(<span style="color: #7060A8;">mod<span style="color: #0000FF;">(<span style="color: #000000;">cycle_length<span style="color: #0000FF;">,<span style="color: #000000;">2<span style="color: #0000FF;">)<span style="color: #0000FF;">==<span style="color: #000000;">0<span style="color: #0000FF;">)</span> |
|||
wdkey = getd_partial_key(0,todo) |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
|||
{walking_distance,space} = getd(wdkey,todo) |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
|||
deld(wdkey,todo) |
|||
<span style="color: #008080;">return</span> <span style="color: #000000;">even_state</span> <span style="color: #0000FF;">==</span> <span style="color: #0000FF;">(<span style="color: #7060A8;">mod<span style="color: #0000FF;">(<span style="color: #000000;">even_count<span style="color: #0000FF;">,<span style="color: #000000;">2<span style="color: #0000FF;">)<span style="color: #0000FF;">==<span style="color: #000000;">0<span style="color: #0000FF;">)</span> |
|||
end while |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span> |
|||
end procedure |
|||
<span style="color: #008080;">procedure</span> <span style="color: #000000;">main<span style="color: #0000FF;">(<span style="color: #0000FF;">)</span> |
|||
function walking_distance(sequence puzzle) |
|||
sequence rkey = repeat(repeat(0,SIZE),SIZE), |
|||
<span style="color: #000000;">puzzle</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{<span style="color: #000000;">15<span style="color: #0000FF;">,<span style="color: #000000;">14<span style="color: #0000FF;">,</span> <span style="color: #000000;">1<span style="color: #0000FF;">,</span> <span style="color: #000000;">6<span style="color: #0000FF;">,</span> |
|||
ckey = repeat(repeat(0,SIZE),SIZE) |
|||
<span style="color: #000000;">9<span style="color: #0000FF;">,<span style="color: #000000;">11<span style="color: #0000FF;">,</span> <span style="color: #000000;">4<span style="color: #0000FF;">,<span style="color: #000000;">12<span style="color: #0000FF;">,</span> |
|||
integer k = 1 |
|||
<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">10<span style="color: #0000FF;">,</span> <span style="color: #000000;">7<span style="color: #0000FF;">,</span> <span style="color: #000000;">3<span style="color: #0000FF;">,</span> |
|||
for i=1 to SIZE do -- rows |
|||
<span style="color: #000000;">13<span style="color: #0000FF;">,</span> <span style="color: #000000;">8<span style="color: #0000FF;">,</span> <span style="color: #000000;">5<span style="color: #0000FF;">,</span> <span style="color: #000000;">2<span style="color: #0000FF;">}</span> |
|||
for j=1 to SIZE do -- columns |
|||
integer tile = puzzle[k] |
|||
<span style="color: #008080;">if</span> <span style="color: #008080;">not</span> <span style="color: #000000;">solvable<span style="color: #0000FF;">(<span style="color: #000000;">puzzle<span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span> |
|||
if tile!=0 then |
|||
<span style="color: #0000FF;">?<span style="color: #000000;">puzzle</span> |
|||
integer row = floor((tile-1)/4)+1, |
|||
<span style="color: #7060A8;">printf<span style="color: #0000FF;">(<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #008000;">"puzzle is not solveable\n"<span style="color: #0000FF;">)</span> |
|||
col = mod(tile-1,4)+1 |
|||
<span style="color: #008080;">else</span> |
|||
rkey[i][row] += 1 |
|||
ckey[j][col] += 1 |
|||
<span style="color: #000000;">generate_mmwd<span style="color: #0000FF;">(<span style="color: #0000FF;">)</span> |
|||
end if |
|||
k += 1 |
|||
<span style="color: #004080;">sequence</span> <span style="color: #000000;">original</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">puzzle</span> |
|||
end for |
|||
<span style="color: #004080;">integer</span> <span style="color: #000000;">space</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">find<span style="color: #0000FF;">(<span style="color: #000000;">0<span style="color: #0000FF;">,<span style="color: #000000;">puzzle<span style="color: #0000FF;">)</span> |
|||
end for |
|||
if getd_index(rkey,mmwd)=0 |
|||
<span style="color: #008080;">for</span> <span style="color: #000000;">lim<span style="color: #0000FF;">=<span style="color: #000000;">walking_distance<span style="color: #0000FF;">(<span style="color: #000000;">puzzle<span style="color: #0000FF;">)</span> <span style="color: #008080;">to</span> <span style="color: #008080;">iff<span style="color: #0000FF;">(<span style="color: #000000;">MTM<span style="color: #0000FF;">?<span style="color: #000000;">43<span style="color: #0000FF;">:<span style="color: #000000;">80<span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span> |
|||
or getd_index(ckey,mmwd)=0 then |
|||
<span style="color: #008080;">if</span> <span style="color: #000000;">iddfs<span style="color: #0000FF;">(<span style="color: #000000;">0<span style="color: #0000FF;">,</span> <span style="color: #000000;">lim<span style="color: #0000FF;">,</span> <span style="color: #000000;">space<span style="color: #0000FF;">,</span> <span style="color: #008000;">'-'<span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
|||
?9/0 -- sanity check |
|||
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
|||
end if |
|||
integer rwd = getd(rkey,mmwd), |
|||
<span style="color: #0000FF;">{<span style="color: #004080;">integer</span> <span style="color: #000000;">n<span style="color: #0000FF;">,</span> <span style="color: #004080;">string</span> <span style="color: #000000;">ns<span style="color: #0000FF;">,</span> <span style="color: #004080;">string</span> <span style="color: #000000;">ans<span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">pack<span style="color: #0000FF;">(<span style="color: #7060A8;">reverse<span style="color: #0000FF;">(<span style="color: #000000;">res<span style="color: #0000FF;">)<span style="color: #0000FF;">)</span> |
|||
cwd = getd(ckey,mmwd) |
|||
return rwd+cwd |
|||
<span style="color: #7060A8;">printf<span style="color: #0000FF;">(<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #008000;">"\n\noriginal:"<span style="color: #0000FF;">)</span> |
|||
end function |
|||
<span style="color: #0000FF;">?<span style="color: #000000;">original</span> |
|||
<span style="color: #004080;">atom</span> <span style="color: #000000;">t</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">time<span style="color: #0000FF;">(<span style="color: #0000FF;">)<span style="color: #0000FF;">-<span style="color: #000000;">t0</span> |
|||
sequence puzzle |
|||
<span style="color: #7060A8;">printf<span style="color: #0000FF;">(<span style="color: #000000;">1<span style="color: #0000FF;">,<span style="color: #008000;">"\n%soptimal solution of %s moves found in %s: %s\n\nresult: "<span style="color: #0000FF;">,</span> |
|||
string res = "" |
|||
<span style="color: #0000FF;">{<span style="color: #008080;">iff<span style="color: #0000FF;">(<span style="color: #000000;">MTM<span style="color: #0000FF;">?<span style="color: #008000;">"mtm-"<span style="color: #0000FF;">:<span style="color: #008080;">iff<span style="color: #0000FF;">(<span style="color: #000000;">STM<span style="color: #0000FF;">?<span style="color: #008000;">"stm-"<span style="color: #0000FF;">:<span style="color: #008000;">"non-"<span style="color: #0000FF;">)<span style="color: #0000FF;">)<span style="color: #0000FF;">,<span style="color: #000000;">ns<span style="color: #0000FF;">,<span style="color: #7060A8;">elapsed<span style="color: #0000FF;">(<span style="color: #000000;">t<span style="color: #0000FF;">)<span style="color: #0000FF;">,<span style="color: #000000;">ans<span style="color: #0000FF;">}<span style="color: #0000FF;">)</span> |
|||
atom t0 = time(), |
|||
<span style="color: #000000;">puzzle</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">original</span> |
|||
t1 = time()+1 |
|||
<span style="color: #000000;">apply_moves<span style="color: #0000FF;">(<span style="color: #000000;">ans<span style="color: #0000FF;">,<span style="color: #000000;">space<span style="color: #0000FF;">)</span> |
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atom tries = 0 |
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<span style="color: #0000FF;">?<span style="color: #000000;">puzzle</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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constant ok = {{0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1}, -- left |
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<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> |
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{0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1}, -- up |
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<span style="color: #000000;">main<span style="color: #0000FF;">(<span style="color: #0000FF;">) |
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{1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0}, -- down |
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<!--</lang>--> |
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{1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,0}} -- right |
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function iddfs(integer step, lim, space, prevmv) |
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if time()>t1 then |
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printf(1,"working... (depth=%d, tries=%d, time=%3ds)\r",{lim,tries,time()-t0}) |
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t1 = time()+1 |
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end if |
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tries += 1 |
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integer d = iff(step==lim?0:walking_distance(puzzle)) |
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if d=0 then |
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return (puzzle==goal) |
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elsif step+d<=lim then |
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for mv=1 to 4 do -- l/u/d/r |
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if prevmv!=(5-mv) -- not l after r or vice versa, ditto u/d |
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and ok[mv][space] then |
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integer nspace = space+{-1,-4,+4,+1}[mv] |
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integer tile = puzzle[nspace] |
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if puzzle[space]!=0 then ?9/0 end if -- sanity check |
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puzzle[space] = tile |
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puzzle[nspace] = 0 |
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if iddfs(step+iff(MTM or not STM?(prevmv!=mv):1),lim,nspace,mv) then |
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res &= "ludr"[mv] |
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return true |
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end if |
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puzzle[nspace] = tile |
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puzzle[space] = 0 |
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end if |
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end for |
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end if |
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return false |
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end function |
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function pack(string s) |
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integer n = length(s), n0 = n |
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for i=1 to 4 do |
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integer ch = "lrud"[i], k |
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while 1 do |
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k = match(repeat(ch,3),s) |
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if k=0 then exit end if |
|||
s[k+1..k+2] = "3" |
|||
n -= 2 |
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end while |
|||
while 1 do |
|||
k = match(repeat(ch,2),s) |
|||
if k=0 then exit end if |
|||
s[k+1] = '2' |
|||
n -= 1 |
|||
end while |
|||
end for |
|||
return {n,iff(MTM?sprintf("%d",n):sprintf("%d(%d)",{n,n0})),s} |
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end function |
|||
procedure apply_moves(string moves, integer space) |
|||
integer move, ch, nspace |
|||
puzzle[space] = 0 |
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for i=1 to length(moves) do |
|||
ch = moves[i] |
|||
if ch>'3' then |
|||
move = find(ch,"ulrd") |
|||
end if |
|||
-- (hint: "r" -> the 'r' does 1 |
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-- "r2" -> the 'r' does 1, the '2' does 1 |
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-- "r3" -> the 'r' does 1, the '3' does 2!) |
|||
for j=1 to 1+(ch='3') do |
|||
nspace = space+{-4,-1,+1,4}[move] |
|||
puzzle[space] = puzzle[nspace] |
|||
space = nspace |
|||
puzzle[nspace] = 0 |
|||
end for |
|||
end for |
|||
end procedure |
|||
function solvable(sequence board) |
|||
integer n = length(board) |
|||
sequence positions = repeat(0,n) |
|||
-- prepare the mapping from each tile to its position |
|||
board[find(0,board)] = n |
|||
for i=1 to n do |
|||
positions[board[i]] = i |
|||
end for |
|||
-- check whether this is an even or odd state |
|||
integer row = floor((positions[16]-1)/4), |
|||
col = (positions[16]-1)-row*4 |
|||
bool even_state = (positions[16]==16) or (mod(row,2)==mod(col,2)) |
|||
-- count the even cycles |
|||
integer even_count = 0 |
|||
sequence visited = repeat(false,16) |
|||
for i=1 to n do |
|||
if not visited[i] then |
|||
-- a new cycle starts at i. Count its length.. |
|||
integer cycle_length = 0, |
|||
next_tile = i |
|||
while not visited[next_tile] do |
|||
cycle_length +=1 |
|||
visited[next_tile] = true |
|||
next_tile = positions[next_tile] |
|||
end while |
|||
even_count += (mod(cycle_length,2)==0) |
|||
end if |
|||
end for |
|||
return even_state == (mod(even_count,2)==0) |
|||
end function |
|||
procedure main() |
|||
puzzle = {15,14, 1, 6, |
|||
9,11, 4,12, |
|||
0,10, 7, 3, |
|||
13, 8, 5, 2} |
|||
if not solvable(puzzle) then |
|||
?puzzle |
|||
printf(1,"puzzle is not solveable\n") |
|||
else |
|||
generate_mmwd() |
|||
sequence original = puzzle |
|||
integer space = find(0,puzzle) |
|||
for lim=walking_distance(puzzle) to iff(MTM?43:80) do |
|||
if iddfs(0, lim, space, '-') then exit end if |
|||
end for |
|||
{integer n, string ns, string ans} = pack(reverse(res)) |
|||
printf(1,"\n\noriginal:") |
|||
?original |
|||
atom t = time()-t0 |
|||
printf(1,"\n%soptimal solution of %s moves found in %s: %s\n\nresult: ", |
|||
{iff(MTM?"mtm-":iff(STM?"stm-":"non-")),ns,elapsed(t),ans}) |
|||
puzzle = original |
|||
apply_moves(ans,space) |
|||
?puzzle |
|||
end if |
|||
end procedure |
|||
main()</lang> |
|||
{{out}} |
{{out}} |
||
<pre> |
<pre> |