#include<iostream> using namespace std; int main() { int n, m, s = 0, a[114][114]; cin >> n >> m; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { cin >> a[i][j]; } } for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (i == 0 || i == n - 1 || j == 0 || j == m - 1) s += a[i][j]; } } cout << s; return 0; }