65 lines
987 B
ObjectPascal
65 lines
987 B
ObjectPascal
program N_queens_problem;
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{$APPTYPE CONSOLE}
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uses
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System.SysUtils;
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var
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i: Integer;
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q: boolean;
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a: array[0..8] of boolean;
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b: array[0..16] of boolean;
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c: array[0..14] of boolean;
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x: array[0..8] of Integer;
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procedure TryMove(i: Integer);
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begin
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var j := 1;
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while True do
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begin
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q := false;
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if a[j] and b[i + j] and c[i - j + 7] then
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begin
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x[i] := j;
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a[j] := false;
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b[i + j] := false;
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c[i - j + 7] := false;
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if i < 8 then
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begin
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TryMove(i + 1);
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if not q then
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begin
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a[j] := true;
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b[i + j] := true;
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c[i - j + 7] := true;
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end;
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end
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else
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q := true;
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end;
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if q or (j = 8) then
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Break;
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inc(j);
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end;
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end;
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begin
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for i := 1 to 8 do
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a[i] := true;
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for i := 2 to 16 do
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b[i] := true;
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for i := 0 to 14 do
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c[i] := true;
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TryMove(1);
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if q then
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for i := 1 to 8 do
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writeln(i, ' ', x[i]);
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readln;
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end.
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