#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <cmath>
#include<set>
#include<math.h>
using namespace std;




int main() {
    int n, m;
    cin >> n >> m;
    vector<vector<int> > v(n, vector<int>(m));
    for (int i = 0; i < n; i++) {

        for (int j = 0; j < m; j++) {
            cin >> v[i][j];
        }

    }
    vector<vector<int> > dp(n, vector<int>(m));

    dp[0][0] = v[0][0];



    for (int i = 1; i < n; i++) {
        dp[i][0] = dp[i - 1][0] + v[i][0];
    }
    for (int  j= 1; j < m; j++) {
        dp[0][j] = dp[0][j-1] + v[0][j];
    }




    for (int i = 1; i < n; i++) {

        for (int j = 1; j < m; j++) {
            dp[i][j] = min(dp[i - 1][j], dp[i][j - 1]) + v[i][j];
        }

    }

    cout << dp[n - 1][m - 1];

}