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#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using ull = unsigned long long;
using db = long double;

using pi = pair<int, int>;
using vi = vector<int>;
using vl = vector<ll>;
using vpi = vector<pi>;

#define mp make_pair
#define pb push_back
#define eb emplace_back
#define x first
#define y second

#define sz(x) int((x).size())
#define all(x) (x).begin(), (x).end()
#define rep(i,a,b) for(int i = (a); i < (b); i++)
#define per(i,a,b) for(int i = (b) - 1; i >= (a); i--)

#ifdef LOCAL
template<class A, class B> auto& operator<<(auto &o, pair<A, B> p) { return o << '(' << p.x << ", " << p.y << ')'; }
template<class... A> auto& operator<<(auto &o, tuple<A...> t) {
	bool is_first = true;
	o << "(";
	apply([&o, &is_first](auto... a) {((o << (is_first ? (is_first = false, "") : ", ") << a), ...);}, t);
	o << ")";
	return o;
}
auto& operator<<(auto& o, auto a) {
	bool is_first = true;
	o << "{";
	for (auto b : a) o << (is_first ? (is_first = false, "") : ", ") << b;
	return o << "}";
}
void dump(auto... x) {
	bool is_first = true;
	((cerr << (is_first ? (is_first = false, "") : ", ") << x), ...) << "\n";
}
#define debug(x...) cerr << "[" #x "]: ", dump(x)
#else
#define debug(...) ;
#endif

template<class T> bool ckmin(T& a, const T& b) { return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }

constexpr ll MOD = 1'000'000'007;

ll fpow(ll a, ll b) {
	ll res = 1;
	for (; b > 0; b >>= 1) {
		if (b & 1) res = (res * a) % MOD;
		a = (a * a) % MOD;
	}
	return res;
}

ll solve_one_permutation(const vi &p) {
	const int n = sz(p);

	vector<bool> vis(n);
	vector<vi> cycles;
	rep(i, 0, n) {
		if (!vis[i]) {
			cycles.resize(sz(cycles) + 1);
			for (int j = i; !vis[j]; j = p[j]) {
				vis[j] = true;
				cycles.back().emplace_back(j);
			}
		}
	}

	ll res = 0;
	rep(i, 0, sz(cycles)) {
		rep(j, 0, sz(cycles)) {
			const auto gcd = __gcd(sz(cycles[i]), sz(cycles[j]));
			const auto lcm = sz(cycles[i]) * sz(cycles[j]) / gcd;
			rep(len, 0, gcd) {
				ll inv = 0, not_inv = 0;
				rep(a, 0, sz(cycles[i])) {
					for (int b = (a - len + gcd) % gcd; b < sz(cycles[j]); b += gcd) {
						if (cycles[i][a] > cycles[j][b]) inv++;
						else not_inv++;
					}
				}
				ll tmp = (inv * not_inv) % MOD;
				res = (res + tmp * fpow(lcm, MOD - 2)) % MOD;
			}
		}
	}
	return res;
}

class fenwick_tree {
private:
	int n;
	vector<int> sum;
	
public:
	fenwick_tree(int _n) : n(_n), sum(_n + 1) {}

	void add(int i, const int value) {
		for (i++; i <= n; i = (i | (i - 1)) + 1) {
			sum[i] += value;
		}
	}

	int get(int i) {
		int result = 0;
		for (i++; i > 0; i &= i - 1) {
			result += sum[i];
		}
		return result;
	}
};

ll get_inversions(const vi &p) {
	const int n = sz(p);
	fenwick_tree tree(n);
	ll res = 0;
	for (int i = n - 1; i >= 0; i--) {
		res += tree.get(p[i]);
		tree.add(p[i], 1);
	}
	return res;
}

vi compose(const vi &a, const vi &b) {
	vi res(sz(a));
	rep(i, 0, sz(res)) {
		res[i] = a[b[i]];
	}
	return res;
}

ll solve_many_permutations(const vector<vi> &p) {
	const int k = sz(p);
	const int n = sz(p[0]);

	vi id(n);
	iota(all(id), 0);

	set<vi> available;
	available.insert(id);
	bool any = true;
	while (any) {
		any = false;
		rep(i, 0, k) {
			vector<vi> new_available;
			for (const auto &other : available) {
				const auto maybe = compose(other, p[i]);
				if (available.find(maybe) == available.end()) {
					new_available.emplace_back(maybe);
				}
			}
			if (!new_available.empty()) {
				any = true;
				available.insert(all(new_available));
			}
		}
	}

	ll res = 0;
	for (const auto &a : available) {
		res = (res + get_inversions(a)) % MOD;
	}
	res = (res * fpow(sz(available), MOD - 2)) % MOD;
	return res;
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);

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

	if (k == 1) {
		vi p(n);
		rep(i, 0, n) cin >> p[i], p[i]--;
		const auto res = solve_one_permutation(p);
		cout << res << "\n";
	}
	else {
		vector<vi> p(k, vi(n));
		rep(i, 0, k) rep(j, 0, n) cin >> p[i][j], p[i][j]--;
		const auto res = solve_many_permutations(p);
		cout << res << "\n";
	}

	return 0;
}