第一题用前缀和处理应该能全a的,但是我贪快就直接暴力加了,过了87% int main() { int n(0), m(0), k(0); cin >> n >> m >> k; vector<vector<int> > mat(n, vector<int>(m, 0)); for (int i = 0; i != n; ++i) { for (int j = 0; j != m; ++j) { cin >> mat[i][j]; ...