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#include <bits/stdc++.h>


using namespace std;


const int MOD = 1'000'000'007;


int expo(int a, int n) {
    int ans = 1;

    while (n) {
        if (n & 1) {
            ans = ((long long) ans * a) % MOD;
        }

        n >>= 1;
        a = ((long long) a * a) % MOD;
    }

    return ans;
}

int revMod(int a) {
    return expo(a, MOD - 2);
}

int solve(int n, vector <vector<int>> &perm) {
    vector <int> comp(n * n), compSize(n * n, 1);
    vector <vector<int>> inComp(n * n);

    for (int i = 0; i < n; i++) for (int j = 0; j < n; j++) if (i != j) {
        int v = n * i + j;

        comp[v] = v;
        inComp[v].push_back(v);
    }

    for (auto &p : perm) {
        for (int i = 0; i < n; i++) {
            int si = n * i, spi = n * p[i];

            for (int j = 0; j < n; j++) if (i != j) {
                int x = comp[si + j], y = comp[spi + p[j]];

                if (x != y) {
                    if (compSize[x] > compSize[y]) {
                        swap(x, y);
                    }

                    compSize[y] += compSize[x];

                    for (int v : inComp[x]) {
                        comp[v] = y;
                        inComp[y].push_back(v);
                    }

                    inComp[x] = vector <int> ();
                }
            }
        }
    }

    vector <int> numAll(n * n, 0), numOrd(n * n, 0);
    for (int i = 0; i < n; i++) for (int j = 0; j < n; j++) if (i != j) {
        int r = comp[n * i + j];

        numAll[r]++;
        numOrd[r] += i < j;
    }

    int ans = 0;
    for (int r = 0; r < n * n; r++) if (numAll[r]) {
        int prod = ((long long) numOrd[r] * (numAll[r] - numOrd[r])) % MOD;
        ans = (ans + (long long) prod * revMod(numAll[r])) % MOD;
    }

    return ans;
}

int main() {
    ios_base::sync_with_stdio(false);

    int n, k;
    cin >> n >> k;

    vector <vector<int>> perm(k, vector <int> (n));
    for (int i = 0; i < k; i++) for (int j = 0; j < n; j++) {
        cin >> perm[i][j]; perm[i][j]--;
    }

    cout << solve(n, perm);

    return 0;
}