8895

8895.cc

#include <iostream>
using namespace std;
long long d[21][21][21];
int main() {
    d[1][1][1] = 1LL;
    for (int i=2; i<=20; i++) {
        for (int j=1; j<=20; j++) {
            for (int k=1; k<=20; k++) {
                d[i][j][k] = d[i-1][j-1][k] + d[i-1][j][k-1] + d[i-1][j][k] * (i-2);
            }
        }
    }
    int t;
    cin >> t;
    while (t--) {
        int n, l, r;
        cin >> n >> l >> r;
        cout << d[n][l][r] << '\n';
    }
    return 0;
}