N-queens problem: Difference between revisions

Content added Content deleted
m (→‎{{header|Uiua}}: Tweaked the algorithm)
Line 16,701: Line 16,701:
`Good` checks that a (maybe partial) solution is valid, by checking that each number is unique, each number+index is unique and each number-index is unique.
`Good` checks that a (maybe partial) solution is valid, by checking that each number is unique, each number+index is unique and each number-index is unique.


Starts with an empty array of values, and stepwise expands and filters.
Starts with an empty array of values, and N times adds each of 0-(N-1) at the end, only keeping those that still validate.


<syntaxhighlight lang="Uiua">
<syntaxhighlight lang="Uiua">
N ← 8
N ← 8
Good ← =1⧻◴[⧻◴ ⟜(∩(⧻◴)⊃(+|-)⇡⧻.) ⟜⧻]
Good ← =1⧻◴[⧻◴⟜(∩(⧻◴)⊃+-⇡⧻.)⟜⧻]
⍥(⊏⊚≡Good.☇1⊞⊂⇡,),[[]]N
⊙◌⍥(⊏⊚≡Good.☇1⊞⊂⇡,),[[]]N
RowString ← ⊂"|"/⊂⍜(⊡|"Q|"◌):↯N"_|"
≡(≡(/(⊂⊂)@|/⊂⍜(⊡|@Q◌):↯:@_)⊸⧻)
≡≡RowString ⟜⧻⊙◌
</syntaxhighlight>
</syntaxhighlight>
{{out}}
{{out}}
<pre>
<pre>
92
92
╭─
╭─
╷ "|Q|_|_|_|_|_|_|_|"
╷ "Q|_|_|_|_|_|_|_"
╷ "|_|_|_|_|Q|_|_|_|"
╷ "_|_|_|_|Q|_|_|_"
"|_|_|_|_|_|_|_|Q|"
"_|_|_|_|_|_|_|Q"
"|_|_|_|_|_|Q|_|_|"
"_|_|_|_|_|Q|_|_"
"|_|_|Q|_|_|_|_|_|"
"_|_|Q|_|_|_|_|_"
"|_|_|_|_|_|_|Q|_|"
"_|_|_|_|_|_|Q|_"
"|_|Q|_|_|_|_|_|_|"
"_|Q|_|_|_|_|_|_"
"|_|_|_|Q|_|_|_|_|"
"_|_|_|Q|_|_|_|_"
"|Q|_|_|_|_|_|_|_|"
"Q|_|_|_|_|_|_|_"
"|_|_|_|_|_|Q|_|_|"
"_|_|_|_|_|Q|_|_"
"|_|_|_|_|_|_|_|Q|"
"_|_|_|_|_|_|_|Q"
"|_|_|Q|_|_|_|_|_|"
"_|_|Q|_|_|_|_|_"
"|_|_|_|_|_|_|Q|_|"
"_|_|_|_|_|_|Q|_"
"|_|_|_|Q|_|_|_|_|"
"_|_|_|Q|_|_|_|_"
"|_|Q|_|_|_|_|_|_|"
"_|Q|_|_|_|_|_|_"
"|_|_|_|_|Q|_|_|_|"
"_|_|_|_|Q|_|_|_"


etc
...etc...
</pre>
</pre>


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