Draw (color in) custom polyominos below or add standard tetrominos

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Polyominos to be fit (click to remove)

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Algorithm X (Dancing Links)

Reduces to an exact cover problem. Only finds exact solutions, but usually gives the best performance when an exact solution exists.

SAT (JavaScript)

Reduces to SAT. Will find partial (inexact) solutions, and is nondeterministic. Uses a JavaScript SAT solver, and usually gives the best performance for small or easy problems.

SAT (Z3)

Reduces to SAT. Will find partial (inexact) solutions, and is deterministic. Solves SAT via a Webassembly build of the Z3 Theorem Prover, and gives better performance for larger problems.

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