#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
struct E {
    int u, v, w;
    bool operator<(const E &e) const { return w > e.w; }
};

struct D {
    vector<int> p, r;
    D(int n) : p(n), r(n, 0) { iota(p.begin(), p.end(), 0); }
    int f(int x) { return p[x] == x ? x : p[x] = f(p[x]); }
    bool u(int x, int y) {
        x = f(x), y = f(y);
        if (x == y) return false;
        if (r[x] < r[y]) swap(x, y);
        p[y] = x;
        if (r[x] == r[y]) r[x]++;
        return true;
    }
};

int md(const vector<int> &a, const vector<int> &b) {
    int d = 0;
    for (int i = 0; i < a.size(); i++) d += abs(a[i] - b[i]);
    return d;
}

ll solve(int n, int k, vector<vector<int>> &p) {
    vector<E> e;
    for (int i = 0; i < n; i++) {
        for (int j = i + 1; j < n; j++) {
            e.push_back({i, j, md(p[i], p[j])});
        }
    }
    sort(e.begin(), e.end());
    D dsu(n);
    ll res = 0;
    for (auto &x : e) {
        if (dsu.u(x.u, x.v)) res += x.w;
    }
    return res;
}

int main() {
    int n, k;
    cin >> n >> k;
    vector<vector<int>> p(n, vector<int>(k));
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < k; j++) {
            cin >> p[i][j];
        }
    }
    cout << solve(n, k, p) << endl;
    return 0;
}