#include <bits/stdc++.h>
#define MOD 1000000007
using namespace std;


int main() {
    int n;
    int k;
    int x;
    cin >> n >> k >> x;
    long z = n-2;
    long answer = (z%MOD * (z+1)%MOD)%MOD;
    answer = answer/2;
    cout << answer << endl;
    return 0;
}