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#define _CRT_SECURE_NO_DEPRECATE

#include <iostream>
#include <vector>
#include <string>
#include <map>
#include <set>
#include <algorithm>

#define ull unsigned long long
#define ll long long

using namespace std;

const int INF = 1e9 + 7;

int main() {
    //freopen("input.txt", "r", stdin);
    //freopen("output.txt", "w", stdout);
    int n, m;
    cin >> m >> n;
    vector<vector<int> > a(n, vector<int>(m));
    vector<vector<int> > d(n, vector<int>(m, INF));
    d[0][0] = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            cin >> a[i][j];
            if (j != 0) {
                d[i][j] = min(d[i][j - 1] + abs(a[i][j] - a[i][j - 1]), d[i][j]);
            }
            if (i != 0) {
                d[i][j] = min(d[i - 1][j] + abs(a[i][j] - a[i - 1][j]), d[i][j]);
            }
        }
    }
    cout << d[n - 1][m - 1];
    return 0;
}