#include <iostream>

using namespace std;
using LL = long long;

constexpr LL INF = 1L << 60;

LL dp[1001][1001];

int main() {
    int N, M;
    cin >> N >> M;

    if (N == 1) {
        cout << 0 << endl;
        exit(0);
    }

    LL A[N + 1][M + 1];
    for (int i = 1; i <= N; i++) {
        for (int j = 1; j <= M; j++) {
            cin >> A[i][j];
        }
    }

    for (int i = 0; i <= N; i++) {
        for (int j = 1; j <= M; j++) {
            if (i == 0) dp[i][j] = 0;
            else dp[i][j] = INF;
        }
    }

    for (int i = 1; i <= N; i++) {
        for (int j = 1; j <= M; j++) {
            for (int k = 1; k <= M; k++) {
                if (j != k) {
                    dp[i][j] = min(dp[i][j], dp[i - 1][k] + A[i][k] + (i != N ? A[i][j] : 0));
                } else {
                    dp[i][j] = min(dp[i][j], dp[i - 1][j] + A[i][j]);
                }
            }
        }
    }

    LL ans = INF;
    for (int i = 1; i <= M; i++) {
        ans = min(ans, dp[N][i]);
    }

    cout << ans << endl;
}