#include <iostream>
using namespace std;

int main()
{
    int n, m;
    cin >> n >> m;
    int matrica[n][m];
    for(int i = 0; i < n; i += 1) {
        for(int j = 0; j < m; j += 1) {
            cin >> matrica[i][j];
        }
    }

    for(int i = 0; i < n; i += 1) {
        for(int j = 0; j < m; j += 1) {
            if(i == j) {
                cout << matrica[i][j] << " ";
            }
        }
    }

    return 0;
}