32 lines
622 B
Text
32 lines
622 B
Text
let solutions n =
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let show board =
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let pr v =
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for i = 1 to n do
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print_string (if i=v then " q" else " _");
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done;
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print_newline() in
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List.iter pr board;
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print_newline() in
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let rec safe i j k = function
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| [] -> true
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| h::t -> h<>i && h<>j && h<>k && safe i (j+1) (k-1) t in
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let rec loop col p =
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for i = 1 to n
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do
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if safe i (i+1) (i-1) p then
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let p' = i::p in
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if col = n then show p'
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else loop (col+1) p'
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done in
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loop 1 [] in
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let n =
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if Array.length Sys.argv > 1
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then int_of_string Sys.argv.(1)
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else 8 in
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solutions n
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