#include <bits/stdc++.h>

using namespace std;

int main() {
    long long n, m, a[2005][2005], f[2005][2005];
    cin >> n >> m;
    for (int i = 1; i <= m; i++) {
        for (int j = 1; j <= n; j++) {
            cin >> a[j][i];
        }
    }
    for (int i = 1; i <= n; i++) {
        f[i - 1][0] = f[i - 1][m];
        for (int j = 1; j <= m; j++) {
            f[i][j] = a[i][j] + min(f[i - 1][j], f[i - 1][j - 1]);
        }
    }
    long long ans = f[n][1];
    for (int i = 2; i <= m; i++) {
        ans = min(ans, f[n][i]);
    }
    cout << ans << endl;
    return 0;
}