#include <iostream>
using namespace std;

int main() {
    int mesec;
    cin >> mesec;
    
    if(mesec == 1) {
        cout << 31 << endl;
    }
    if(mesec == 2) {
        cout << 28 << endl;
    }
    if(mesec == 3) {
        cout << 31 << endl;
    }
    if(mesec == 4) {
        cout << 30 << endl;
    }
    if(mesec == 5) {
        cout << 31 << endl;
    }
    if(mesec == 6) {
        cout << 30 << endl;
    }
    if(mesec == 7) {
        cout << 31 << endl;
    }
    if(mesec == 8) {
        cout << 31 << endl;
    }
    if(mesec == 9) {
        cout << 30 << endl;
    }
    if(mesec == 10) {
        cout << 31 << endl;
    }
    if(mesec == 11) {
        cout << 30 << endl;
    }
    if(mesec == 12) {
        cout << 31 << endl;
    }
    
    
    return 0;
}