{"trustable":false,"sections":[{"title":"","value":{"format":"PLAIN","content":"题干:A university network is composed of N computers. System administrators gathered information on the traffic between nodes, and carefully divided the network into two subnetworks in order to minimize traffic between parts.\nA disgruntled computer science student Vasya, after being expelled from the university, decided to have his revenge. He hacked into the university network and decided to reassign computers to maximize the traffic between two subnetworks.\nUnfortunately, he found that calculating such worst subdivision is one of those problems he, being a student, failed to solve. So he asks you, a more successful CS student, to help him.\nThe traffic data are given in the form of matrix C, where Cij is the amount of data sent between ith and jth nodes (Cij \u003d Cji, Cii \u003d 0). The goal is to divide the network nodes into the two disjointed subsets A and B so as to maximize the sum ∑Cij (i∈A,j∈B).\n\n输入:The first line of input contains a number of nodes N (2 \u003c\u003d N \u003c\u003d 20). The following N lines, containing N space-separated integers each, represent the traffic matrix C (0 \u003c\u003d Cij \u003c\u003d 10000).\nOutput file must contain a single integer -- the maximum traffic between the subnetworks.\n\n输出:Output must contain a single integer -- the maximum traffic between the subnetworks."}},{"title":"","value":{"format":"PLAIN","content":"有n台电脑(2\u003c\u003dn\u003c\u003d20),任意两台电脑i,j之间都有网线连接,价值为Cij(0\u003c\u003dCij\u003c\u003d10000),保证Cij\u003dCji,且Cii\u003d0。\n你需要将所有电脑分为两部分,对于所有不属于同一部分的两台电脑i,j,能够获得它们的价值Cij。要求使得总价值最大,输出该总价值。"}},{"title":"Input","value":{"format":"PLAIN","content":"第一行一个整数n。\n接下来n行,每行有n个整数,表示Cij。"}},{"title":"Output","value":{"format":"PLAIN","content":"仅一行,一个整数,表示最大总价值。"}},{"title":"Sample Input","value":{"format":"PLAIN","content":"3\n0 50 30\n50 0 40\n30 40 0"}},{"title":"Sample Output","value":{"format":"PLAIN","content":"90"}}]}