Jip J. Dekker
f2a1c4e389
git-subtree-dir: software/mza git-subtree-split: f970a59b177c13ca3dd8aaef8cc6681d83b7e813
34 lines
807 B
MiniZinc
34 lines
807 B
MiniZinc
% RUNS ON mzn20_fd
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% RUNS ON mzn-fzn_fd
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% RUNS ON mzn20_mip
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% Copied from the queens.mzn benchmark.
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%
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% In some very rare cases some literals in MiniSAT are labeled during
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% backjumping but never actually propagated
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% (if invoke is never entered again),
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% which leads to the output of flatzinc showing unfixed int variables.
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%
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%
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int: n = 20; % The number of queens.
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array [1..n] of var 1..n: q;
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predicate
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noattack(int: i, int: j, var int: qi, var int: qj) =
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qi != qj /\
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qi + i != qj + j /\
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qi - i != qj - j;
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constraint
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forall (i in 1..n, j in i+1..n) (
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noattack(i, j, q[i], q[j])
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);
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solve satisfy;
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output ["% ", show(n), "-queens:\n"] ++
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["% "] ++ [show(q[i]) ++ " " | i in 1..n] ++
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["\n%\n"] ++
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["q = ", show(q), ";\n"];
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