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#include <bits/stdc++.h>
#define dbg(x) " [" << #x << ": " << (x) << "] "
using namespace std;
using ll = long long;
template<typename A, typename B>
ostream& operator<<(ostream& out, const pair<A,B>& p) {
    return out << "(" << p.first << ", " << p.second << ")";
}
template<typename T>
ostream& operator<<(ostream& out, const vector<T>& c) {
    out << "{";
    for(auto it = c.begin(); it != c.end(); it++) {
        if(it != c.begin()) out << ", ";
        out << *it;
    }
    return out << "}";
}

const int mod = 1e9 + 7;

ll bp(ll a, ll b) {
    ll r = 1;
    while(b) {
        if(b & 1) r = r * a % mod;
        b /= 2;
        a = a * a % mod;
    }
    return r;
}

int compute(int n, vector<int> a, vector<int> b) {
    int x = a.size();
    int y = b.size();
    ll r = 0;
    int g = gcd(x, y);
    int l = x * y / g;
    vector<int> elem(g);
    for(int diff = 0; diff < g; diff++) {
        for(int rep = 0; rep < l; rep++) {
            if(a[rep % x] > b[(diff + rep) % y]) elem[diff]++;
        }
        elem[diff] *= g;
    }
    for(int diff = 0; diff < y; diff++) {
        ll pos = 0;
        for(int i = 0; i < x; i++) {
            int j = (i + diff) % y;
            if(a[i] < b[j]) pos++;
        }
        r += pos * elem[diff % g];
        r %= mod;
    }
    return r * bp(x * y, mod - 2) % mod;
}

void solve_one(int n) {
    vector<int> u(n);
    vector<int> v(n);
    for(int i = 0; i < n; i++) {
        cin >> v[i];
        v[i]--;
    }

    vector<vector<int>> cyc;
    for(int i = 0; i < n; i++) {
        if(u[i]) continue;
        int j = i;
        vector<int> c;
        while(!u[j]) {
            c.push_back({v[j]});
            u[j] = 1;
            j = v[j];
        }
        cyc.push_back(c);
    }

    int ans = 0;
    for(int i = 0; i < cyc.size(); i++) {
        for(int j = i; j < cyc.size(); j++) {
            ll x = compute(n, cyc[i], cyc[j]);
            if(i < j) x = 2 * x % mod;
            ans = (ans + x) % mod;
        }
    }
    cout << ans << endl;
}

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

void solve_brute(int n, int k) {
    vector<vector<int>> v(k);
    for(int i = 0; i < k; i++) {
        v[i].resize(n);
        for(int j = 0; j < n; j++) {
            cin >> v[i][j];
            v[i][j]--;
        }
    }

    set<vector<int>> st;
    vector<int> start(n);
    iota(start.begin(), start.end(), 0);
    queue<vector<int>> q;
    q.push(start);
    st.insert(start);

    ll ans = 0;
    ll cnt = 0;

    while(!q.empty()) {
        auto x = q.front();
        q.pop();

        cnt++;
        if(cnt >= mod) cnt -= mod;
        for(int i = 0; i < n; i++) {
            for(int j = i + 1; j < n; j++) {
                if(x[i] > x[j]) ans++;
            }
        }
        if(ans >= mod) ans -= mod;

        for(int i = 0; i < k; i++) {
            auto y = compose(x, v[i]);
            if(!st.contains(y)) {
                st.insert(y);
                q.push(y);
            }
        }
    }

    ans = ans * bp(cnt, mod - 2) % mod;
    cout << ans << endl;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    int n, k;
    cin >> n >> k;
    if(k == 1) {
        solve_one(n);
        return 0;
    }
    solve_brute(n, k);

    return 0;
}