http://codeforces.com/problemset/problem/429/B 挺简单的题,先求出四个点到每一点的最大和,然后枚举每一点,取和最大值. 注意两条路相交的点有且只有一个,这点的数值不加. #include<iostream> #include<algorithm> using namespace std; ][]; ][] = {},e1[][] = {},s2[][] = {},e2[][] = {}; int main() { int n,m; ci…