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// [2A] Grupa permutacji, Kamil Debowski
#include <bits/stdc++.h>
using namespace std;
#define sim template < class c
#define ris return * this
#define dor > debug & operator <<
#define eni(x) sim > typename \
  enable_if<sizeof dud<c>(0) x 1, debug&>::type operator<<(c i) {
sim > struct rge { c b, e; };
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c* x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
#ifdef LOCAL
~debug() { cerr << endl; }
eni(!=) cerr << boolalpha << i; ris; }
eni(==) ris << range(begin(i), end(i)); }
sim, class b dor(pair < b, c > d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (auto it = d.b; it != d.e; ++it)
	*this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
#else
sim dor(const c&) { ris; }
#endif
};
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "
// debug & operator << (debug & dd, P p) { dd << "(" << p.x << ", " << p.y << ")"; return dd; }

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

int my_pow(int a, int b) {
	int r = 1;
	while (b) {
		if (b % 2) {
			r = (long long) r * a % MOD;
		}
		a = (long long) a * a % MOD;
		b /= 2;
	}
	return r;
}
int my_inv(int a) { return my_pow(a, MOD - 2); }

int main() {
	int n, k;
	scanf("%d%d", &n, &k);
	// vector<vector<int>> p(k, vector<int>(n));;;
	// for (int i = 0; i < k; i++) {
		// for (int j = 0; j < n; j++) {
			// scanf("%d", &p[i][j]);
			// p[i][j]--;
		// }
	// }
	// Find & Union
	vector<int> g(n * n);
	vector<vector<int>> inv(n * n);
	for (int a = 0; a < n * n; a++) {
		g[a] = a;
		inv[a] = {a};
	}
	auto uni = [&](int a, int b) {
		// debug() << imie(a) imie(b);
		a = g[a];
		b = g[b];
		if (a == b) {
			return;
		}
		if (inv[a].size() > inv[b].size()) {
			swap(a, b);
		}
		inv[b].insert(inv[b].end(), inv[a].begin(), inv[a].end());
		for (int x : inv[a]) {
			// inv[b].push_back(x);
			g[x] = b;
		}
		inv[a].clear();
	};
	auto getHash = [&](int i, int j) { return n * i + j; };
	for (int row = 0; row < k; row++) {
		// cerr << row << " ";
		vector<int> p(n);
		for (int i = 0; i < n; i++) {
			scanf("%d", &p[i]);
			p[i]--;
		}
		for (int i = 0; i < n; i++) {
			for (int j = 0; j < n; j++) {
				// if (i > 50 && j > 50) break;
				// if (i != j) {
				if (i != j && g[p[i]*n+p[j]] != g[i*n+j]) {
					int x = getHash(p[i], p[j]);
					int y = getHash(i, j);
					uni(x, y);
				}
				// }
			}
		}
	}
	for (int i = 0; i < n; i++) {
		assert((int) inv[getHash(i, i)].size() == 1);
	}
	int answer = 0;
	vector<int> memo(n * n + 1);
	for (int a = 0; a < n * n; a++) {
		if ((int) inv[a].size() > 1) {
			int good = 0, bad = 0;
			for (int x : inv[a]) {
				if (x / n < x % n) {
					good++;
				}
				else {
					bad++;
				}
			}
			if (!memo[good+bad]) {
				memo[good+bad] = my_inv(good+bad);
			}
			answer = (answer + (long long) bad * good % MOD * memo[good+bad]) % MOD;
			// answer += (double) bad / (good + bad);
			// debug() << imie(i) imie(j) imie(good) imie(bad);
		}
	}
	// printf("%.10lf\n", answer);
	cout << answer << endl;
}