b_9095.cpp

#include <iostream>

using namespace std;

int factorial(int num);

int main() {
    int input_iter;

    // input
    cin >> input_iter;
    int num_arr[input_iter];
    int result_arr[input_iter];
    for (int i = 0; i < input_iter; i++){
        cin >> num_arr[i];
    }
    
    for (int iter = 0; iter < input_iter; iter++) {
        int &curr_num = num_arr[iter], &result = result_arr[iter], numCount[3] = {0, };
        result = 0;

        for (int i = curr_num / 3; i >= 0; i --) {
            for(int j = (curr_num - i * 3) / 2; j >= 0; j--) {
                int k = curr_num - (i * 3 + j * 2);
                result += factorial(i + j + k) / (factorial(i) * factorial(j) * factorial(k));
            }
        }
        cout << result << endl;
    }
}




int factorial(int num) {
    int result = 1;
    if (num == 0) {
        return 1;
    }
    for(int i = 1; i <= num; i++ ) {
        result *= i;
    }
    return result;
}

백준 9095 : 1, 2, 3 더하기