答案

#include <iostream>
using namespace std;
int main(){
    int n, i = 1, cnt = 0;
    cin >> n;
    int arr[13] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
    for(int i = 1; i <= 12; i++){
        if((12 + cnt + n) % 7 == 5){
            cout << i << endl;
        }
        cnt += arr[i];
    }
 	return 0;
}