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Fill the N×N grid with the numbers 1 to N. No number may repeat in a row or column. In addition, the numbers in each bold cage must produce the target in its top-left corner using the operator shown. A single-cell cage with just a number simply contains that number.

− and ÷ cages always have exactly two cells: subtract (or divide) the smaller number from the larger to get the target. For example, "2÷" can be 1 and 2, 2 and 4, or 3 and 6. + and × cages can have three or more cells; add (or multiply) them all to get the target. A number may repeat inside a cage as long as the copies are in different rows and columns.

It uses the same family of rules (a Latin square plus arithmetic cages). Numbers run from 1 to N, the operators are + − × ÷, and − and ÷ appear only in two-cell cages.

Yes. Every puzzle is built to have a unique solution (each time the cages are drawn, we check that only one solution exists). You never need to guess — logic alone is enough.

By the time from opening the puzzle to filling it in correctly, fastest first. You only need a nickname, and you can submit up to 30 times a day per size. The server checks that your answer follows the rules.