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#include <iostream>
#include <vector>
#include <cassert>
#include <unordered_map>

using namespace std;

const long long modd = 1'000'000'007;

long long mpow(long long x, long long exp) {
    if(exp == 0)
        return 1;
    long long result = mpow(x, exp / 2);
    result = result * result % modd;
    if(exp & 1)
        result = result * x % modd;
    return result;
}

const long long mod = 1021043935909;

unordered_map<long long, bool>m;

vector<vector<int>>perms;

vector<int> compose(vector<int>a, vector<int>b) {
    int n = a.size();
    vector<int>c(n);
    for(int i = 0; i < n; i++)
        c[i] = a[b[i]];
    return c;
}

int inv(vector<int>&v) {
    int n = v.size(), result = 0;
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < i; j++) {
            result += v[i] < v[j];
        }
    }
    return result;
}

long long h(vector<int>&v) {
    int n = v.size();
    long long result = 0;
    for(int x : v)
        result = (result * n + x) % mod;
    return result;
}

long long total_inv = 0;
long long count = 0;

void rec(vector<int>v) {
    long long hh = h(v);
    if(m[hh] == true)
        return;
    count++;
    total_inv += inv(v);
    m[hh] = true;
    for(auto p : perms)
        rec(compose(v, p));
}

int main() {
    ios_base::sync_with_stdio(0);
    int n, k; cin >> n >> k;
    perms.resize(k);
    for(int i = 0; i < k; i++) {
        perms[i].resize(n);
        for(int &x : perms[i]) {
            cin >> x;
            x--;
        }
    }
    vector<int>id(n);
    for(int i = 0; i < n; i++)
        id[i] = i;

    rec(id);

    cout << total_inv * mpow(count, modd - 2) % modd << "\n";
}