单选题库

#include <iostream>
using namespace std;
int main() {
    int cnt = 0;
    for (int x = 0; x <= 10; x++)
        for (int y = 0; y <= 10; y++)
            for (int z = 0; z <= 10; z++)
                if (x + y + z <= 15)
                    cnt++;
    cout << cnt << endl;
    return 0;
}

int gcd(int m, int n) {
    if (m == 0)
        return n;
    return gcd(n % m, m);
}

bool notPrime[N] = {false};
void sieve() {
    for (int n = 2; n * n < N; n++)
        if (!notPrime[n])
            for (int i = n * n; i < N; i += n)
                notPrime[i] = true;
}