#include <bits/stdc++.h>
using namespace std;
int main(){
	//闰年部分判断 
	char n;
	int m;
	cin>>m>>n;
	if(n == '1'||n=='3'||n == '5'||n=='7'||n == '8'||n=='10'||n == '12'){
		cout<<"31";
		return 0;
	}else if(n == '4'||n=='6'||n == '9'||n=='11'){
		cout<<"30";
		return 0;
	}
	else if((m%4 == 0&&m%100!=0)||m%400 == 0){
		cout<<"29";
	}	
	else{
		cout<<"28";
	}
}