Not Greedy algorithm for Set Cover

Details about my sets: each set have exactly M elements, and each element belongs to exactly N sets.

I need a Non greedy algorithm to compute t开发者_如何学运维he size of the minimal set cover.

is there a good algorithm? (for my special case)

thanks.

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The hardness results and probably the inapproximability results (perhaps with a worse constant) apply even to your special case. Use a solver for mixed-integer programs such as GLPK.