#include <iostream> #include <vector> using namespace std; int main() { int n, m; cin >> n >> m; int a[n][m]; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { cin >> a[i][j]; } } long long sum = 0; //这里要longlong,后面很大 for (int i = 0; i < n; i++) { for (int j = 0; j < m ; j++) { sum += a[i][j]; } } cout << sum; }