#include<bits/stdc++.h> 
using namespace std;
int main(){
	int y,m;
	scanf("%d-%d",&y,&m);
	if(m==2){
	if((y%4==0&&y%100!=0)||y%400==0)	
	   printf("29\n");
	else printf("28\n");}
	else {switch(m){
	case 1: case 3: case 5: case 7: case 8: case 10: case 12: 
	printf("31\n");break;
	case 4: case 6: case 9: case 11:printf("30\n");break;}
	}

	            












	return 0;
}
/**************************************************************
	Problem: 2096
	User: zhangchenhao
	Language: C++
	Result: Wrong Answer
****************************************************************/