문제
풀이
#include <iostream>
using namespace std;
bool solve(void) {
long long n, k; cin >> n >> k;
if (n == 0 && k == 0) return false;
long long ans = 1;
for (int i=1; i<=k && i<=n-k; i++) {
ans = ans * (n-i+1) / i;
}
cout << ans << "\n";
return true;
}
int main(void) {
ios::sync_with_stdio(false);
cin.tie(nullptr);
while (solve());
return 0;
}