#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define llong long long

int main() {
    int n, m;
    cin >> n >> m;

    llong result = 1LL;
    const llong divisor = 1e9 + 7;
    rep(i, m) {
        result *= n-i;
        result %= divisor;
    }

    cout << result << "\n";
}