Knight's tour: Difference between revisions

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m (→‎{{header|Phix}}: added syntax colouring, marked p2js compatible)
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=={{header|Phix}}==
=={{header|Phix}}==
This is pretty fast (<<1s) up to size 48, before some sizes start to take quite some time to complete. It will even solve a 200x200 in 0.67s
This is pretty fast (<<1s) up to size 48, before some sizes start to take quite some time to complete. It will even solve a 200x200 in 0.67s
<lang Phix>constant size = 8
<!--<lang Phix>(phixonline)-->
<span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span>
constant nchars = length(sprintf(" %d",size*size))
<span style="color: #008080;">constant</span> <span style="color: #000000;">size</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">8</span><span style="color: #0000FF;">,</span>
constant fmt = sprintf(" %%%dd",nchars-1)
<span style="color: #000000;">nchars</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">sprintf</span><span style="color: #0000FF;">(</span><span style="color: #008000;">" %d"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">size</span><span style="color: #0000FF;">*</span><span style="color: #000000;">size</span><span style="color: #0000FF;">)),</span>
constant blank = repeat(' ',nchars)
<span style="color: #000000;">fmt</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">sprintf</span><span style="color: #0000FF;">(</span><span style="color: #008000;">" %%%dd"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">nchars</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">),</span>

<span style="color: #000000;">blank</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #008000;">' '</span><span style="color: #0000FF;">,</span><span style="color: #000000;">nchars</span><span style="color: #0000FF;">)</span>
-- to simplify output, each square is nchars
sequence board = repeat(repeat(' ',size*nchars),size)
<span style="color: #000080;font-style:italic;">-- to simplify output, each square is nchars</span>
-- keep current counts, immediately backtrack if any hit 0
<span style="color: #004080;">sequence</span> <span style="color: #000000;">board</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #008000;">' '</span><span style="color: #0000FF;">,</span><span style="color: #000000;">size</span><span style="color: #0000FF;">*</span><span style="color: #000000;">nchars</span><span style="color: #0000FF;">),</span><span style="color: #000000;">size</span><span style="color: #0000FF;">)</span>
-- (in line with the above, we only use every nth entry)
<span style="color: #000080;font-style:italic;">-- keep current counts, immediately backtrack if any hit 0
sequence warnsdorffs = repeat(repeat(0,size*nchars),size)
-- (in line with the above, we only use every nth entry)</span>

<span style="color: #004080;">sequence</span> <span style="color: #000000;">warnsdorffs</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">size</span><span style="color: #0000FF;">*</span><span style="color: #000000;">nchars</span><span style="color: #0000FF;">),</span><span style="color: #000000;">size</span><span style="color: #0000FF;">)</span>
constant ROW = 1, COL = 2
constant moves = {{-1,-2},{-2,-1},{-2,1},{-1,2},{1,2},{2,1},{2,-1},{1,-2}}
<span style="color: #008080;">constant</span> <span style="color: #000000;">ROW</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">COL</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">2</span><span style="color: #0000FF;">,</span>

<span style="color: #000000;">moves</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{{-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,-</span><span style="color: #000000;">2</span><span style="color: #0000FF;">},{-</span><span style="color: #000000;">2</span><span style="color: #0000FF;">,-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">},{-</span><span style="color: #000000;">2</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">},{-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">2</span><span style="color: #0000FF;">},{</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">2</span><span style="color: #0000FF;">},{</span><span style="color: #000000;">2</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">},{</span><span style="color: #000000;">2</span><span style="color: #0000FF;">,-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">},{</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,-</span><span style="color: #000000;">2</span><span style="color: #0000FF;">}}</span>
function onboard(integer row, integer col)
return row>=1 and row<=size and col>=nchars and col<=nchars*size
<span style="color: #008080;">function</span> <span style="color: #000000;">onboard</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">row</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">col</span><span style="color: #0000FF;">)</span>
end function
<span style="color: #008080;">return</span> <span style="color: #000000;">row</span><span style="color: #0000FF;">>=</span><span style="color: #000000;">1</span> <span style="color: #008080;">and</span> <span style="color: #000000;">row</span><span style="color: #0000FF;"><=</span><span style="color: #000000;">size</span> <span style="color: #008080;">and</span> <span style="color: #000000;">col</span><span style="color: #0000FF;">>=</span><span style="color: #000000;">nchars</span> <span style="color: #008080;">and</span> <span style="color: #000000;">col</span><span style="color: #0000FF;"><=</span><span style="color: #000000;">nchars</span><span style="color: #0000FF;">*</span><span style="color: #000000;">size</span>

<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
procedure init_warnsdorffs()
integer nrow,ncol
<span style="color: #008080;">procedure</span> <span style="color: #000000;">init_warnsdorffs</span><span style="color: #0000FF;">()</span>
for row=1 to size do
<span style="color: #008080;">for</span> <span style="color: #000000;">row</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #000000;">size</span> <span style="color: #008080;">do</span>
for col=nchars to nchars*size by nchars do
<span style="color: #008080;">for</span> <span style="color: #000000;">col</span><span style="color: #0000FF;">=</span><span style="color: #000000;">nchars</span> <span style="color: #008080;">to</span> <span style="color: #000000;">nchars</span><span style="color: #0000FF;">*</span><span style="color: #000000;">size</span> <span style="color: #008080;">by</span> <span style="color: #000000;">nchars</span> <span style="color: #008080;">do</span>
for move=1 to length(moves) do
<span style="color: #008080;">for</span> <span style="color: #000000;">move</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">moves</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
nrow = row+moves[move][ROW]
<span style="color: #004080;">integer</span> <span style="color: #000000;">nrow</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">row</span><span style="color: #0000FF;">+</span><span style="color: #000000;">moves</span><span style="color: #0000FF;">[</span><span style="color: #000000;">move</span><span style="color: #0000FF;">][</span><span style="color: #000000;">ROW</span><span style="color: #0000FF;">],</span>
ncol = col+moves[move][COL]*nchars
<span style="color: #000000;">ncol</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">col</span><span style="color: #0000FF;">+</span><span style="color: #000000;">moves</span><span style="color: #0000FF;">[</span><span style="color: #000000;">move</span><span style="color: #0000FF;">][</span><span style="color: #000000;">COL</span><span style="color: #0000FF;">]*</span><span style="color: #000000;">nchars</span>
if onboard(nrow,ncol) then
<span style="color: #008080;">if</span> <span style="color: #000000;">onboard</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">,</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
warnsdorffs[row][col] += 1
<span style="color: #000000;">warnsdorffs</span><span style="color: #0000FF;">[</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">][</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end procedure
<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span>

atom t0 = time()
<span style="color: #004080;">atom</span> <span style="color: #000000;">t0</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">time</span><span style="color: #0000FF;">(),</span>
integer tries = 0
<span style="color: #000000;">t1</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">time</span><span style="color: #0000FF;">()+</span><span style="color: #000000;">1</span>
atom t1 = time()+1
<span style="color: #004080;">integer</span> <span style="color: #000000;">tries</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span>
function solve(integer row, integer col, integer n)
<span style="color: #008080;">function</span> <span style="color: #000000;">solve</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">row</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">col</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">n</span><span style="color: #0000FF;">)</span>
integer nrow, ncol
<span style="color: #008080;">if</span> <span style="color: #7060A8;">time</span><span style="color: #0000FF;">()></span><span style="color: #000000;">t1</span> <span style="color: #008080;">and</span> <span style="color: #7060A8;">platform</span><span style="color: #0000FF;">()!=</span><span style="color: #004600;">JS</span> <span style="color: #008080;">then</span>
if time()>t1 then
<span style="color: #0000FF;">?{</span><span style="color: #000000;">row</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">floor</span><span style="color: #0000FF;">(</span><span style="color: #000000;">col</span><span style="color: #0000FF;">/</span><span style="color: #000000;">nchars</span><span style="color: #0000FF;">),</span><span style="color: #000000;">n</span><span style="color: #0000FF;">,</span><span style="color: #000000;">tries</span><span style="color: #0000FF;">}</span>
?{row,floor(col/nchars),n,tries}
<span style="color: #7060A8;">puts</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">join</span><span style="color: #0000FF;">(</span><span style="color: #000000;">board</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"\n"</span><span style="color: #0000FF;">))</span>
puts(1,join(board,"\n"))
<span style="color: #000000;">t1</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">time</span><span style="color: #0000FF;">()+</span><span style="color: #000000;">1</span>
t1 = time()+1
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
-- if wait_key()='!' then ?9/0 end if
<span style="color: #000000;">tries</span><span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span>
end if
<span style="color: #008080;">if</span> <span style="color: #000000;">n</span><span style="color: #0000FF;">></span><span style="color: #000000;">size</span><span style="color: #0000FF;">*</span><span style="color: #000000;">size</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #000000;">1</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
tries+= 1
<span style="color: #004080;">sequence</span> <span style="color: #000000;">wmoves</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
if n>size*size then return 1 end if
<span style="color: #004080;">integer</span> <span style="color: #000000;">nrow</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">ncol</span>
sequence wmoves = {}
<span style="color: #008080;">for</span> <span style="color: #000000;">move</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">moves</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
for move=1 to length(moves) do
<span style="color: #000000;">nrow</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">row</span><span style="color: #0000FF;">+</span><span style="color: #000000;">moves</span><span style="color: #0000FF;">[</span><span style="color: #000000;">move</span><span style="color: #0000FF;">][</span><span style="color: #000000;">ROW</span><span style="color: #0000FF;">]</span>
nrow = row+moves[move][ROW]
<span style="color: #000000;">ncol</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">col</span><span style="color: #0000FF;">+</span><span style="color: #000000;">moves</span><span style="color: #0000FF;">[</span><span style="color: #000000;">move</span><span style="color: #0000FF;">][</span><span style="color: #000000;">COL</span><span style="color: #0000FF;">]*</span><span style="color: #000000;">nchars</span>
ncol = col+moves[move][COL]*nchars
<span style="color: #008080;">if</span> <span style="color: #000000;">onboard</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">,</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">)</span>
if onboard(nrow,ncol)
<span style="color: #008080;">and</span> <span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">][</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">]=</span><span style="color: #008000;">' '</span> <span style="color: #008080;">then</span>
and board[nrow][ncol]=' ' then
<span style="color: #000000;">wmoves</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">wmoves</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">warnsdorffs</span><span style="color: #0000FF;">[</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">][</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">],</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">,</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">})</span>
wmoves = append(wmoves,{warnsdorffs[nrow][ncol],nrow,ncol})
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #000000;">wmoves</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">sort</span><span style="color: #0000FF;">(</span><span style="color: #000000;">wmoves</span><span style="color: #0000FF;">)</span>
wmoves = sort(wmoves)
-- avoid creating orphans
<span style="color: #000080;font-style:italic;">-- avoid creating orphans</span>
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">wmoves</span><span style="color: #0000FF;">)<</span><span style="color: #000000;">2</span> <span style="color: #008080;">or</span> <span style="color: #000000;">wmoves</span><span style="color: #0000FF;">[</span><span style="color: #000000;">2</span><span style="color: #0000FF;">][</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]></span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span>
if length(wmoves)<2 or wmoves[2][1]>1 then
<span style="color: #008080;">for</span> <span style="color: #000000;">m</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">wmoves</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
for m=1 to length(wmoves) do
<span style="color: #0000FF;">{?,</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">,</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">wmoves</span><span style="color: #0000FF;">[</span><span style="color: #000000;">m</span><span style="color: #0000FF;">]</span>
{?,nrow,ncol} = wmoves[m]
<span style="color: #000000;">warnsdorffs</span><span style="color: #0000FF;">[</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">][</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">-=</span> <span style="color: #000000;">1</span>
warnsdorffs[nrow][ncol] -= 1
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end for
<span style="color: #008080;">for</span> <span style="color: #000000;">m</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">wmoves</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
for m=1 to length(wmoves) do
<span style="color: #0000FF;">{?,</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">,</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">wmoves</span><span style="color: #0000FF;">[</span><span style="color: #000000;">m</span><span style="color: #0000FF;">]</span>
{?,nrow,ncol} = wmoves[m]
<span style="color: #004080;">integer</span> <span style="color: #000000;">scol</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ncol</span><span style="color: #0000FF;">-</span><span style="color: #000000;">nchars</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span>
board[nrow][ncol-nchars+1..ncol] = sprintf(fmt,n)
<span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">][</span><span style="color: #000000;">scol</span><span style="color: #0000FF;">..</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">sprintf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">fmt</span><span style="color: #0000FF;">,</span><span style="color: #000000;">n</span><span style="color: #0000FF;">)</span>
if solve(nrow,ncol,n+1) then return 1 end if
<span style="color: #008080;">if</span> <span style="color: #000000;">solve</span><span style="color: #0000FF;">(</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">,</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">,</span><span style="color: #000000;">n</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #000000;">1</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
board[nrow][ncol-nchars+1..ncol] = blank
<span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">][</span><span style="color: #000000;">scol</span><span style="color: #0000FF;">..</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">blank</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
for m=1 to length(wmoves) do
<span style="color: #008080;">for</span> <span style="color: #000000;">m</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">wmoves</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
{?,nrow,ncol} = wmoves[m]
<span style="color: #0000FF;">{?,</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">,</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">wmoves</span><span style="color: #0000FF;">[</span><span style="color: #000000;">m</span><span style="color: #0000FF;">]</span>
warnsdorffs[nrow][ncol] += 1
<span style="color: #000000;">warnsdorffs</span><span style="color: #0000FF;">[</span><span style="color: #000000;">nrow</span><span style="color: #0000FF;">][</span><span style="color: #000000;">ncol</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
return 0
<span style="color: #008080;">return</span> <span style="color: #000000;">0</span>
end function
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>

init_warnsdorffs()
<span style="color: #000000;">init_warnsdorffs</span><span style="color: #0000FF;">()</span>
board[1][nchars] = '1'
<span style="color: #000000;">board</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">][</span><span style="color: #000000;">nchars</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">'1'</span>
if solve(1,nchars,2) then
<span style="color: #008080;">if</span> <span style="color: #000000;">solve</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">nchars</span><span style="color: #0000FF;">,</span><span style="color: #000000;">2</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
puts(1,join(board,"\n"))
<span style="color: #7060A8;">puts</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">join</span><span style="color: #0000FF;">(</span><span style="color: #000000;">board</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"\n"</span><span style="color: #0000FF;">))</span>
printf(1,"\nsolution found in %d tries (%3.2fs)\n",{tries,time()-t0})
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"\nsolution found in %d tries (%3.2fs)\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">tries</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">time</span><span style="color: #0000FF;">()-</span><span style="color: #000000;">t0</span><span style="color: #0000FF;">})</span>
else
<span style="color: #008080;">else</span>
puts(1,"no solutions found\n")
<span style="color: #7060A8;">puts</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"no solutions found\n"</span><span style="color: #0000FF;">)</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
{} = wait_key()</lang>
<!--</lang>-->
{{out}}
{{out}}
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