URAL1076. Trash Two-point graph perfect Match

There are n trash cans, each garbage bin is loaded with n kinds of rubbish, each rubbish bin each kind of rubbish has weight, request to put all rubbish bin of the same rubbish in the same rubbish bin of the minimum cost, where move from the first bucket to the J bucket of waste weight, i==j spend 0 statistics each kind of garbage sum, If you pour the K-type rubbish into the F-bin, the cost is K-f (k) (the rubbish you already have is not to be poured). Then there is a simple two-part chart to build.