题解

#include<iostream>
using namespace std;
int main(){
int a,b;
cin>>a>>b;
if(b2){
if(a%4000||(a%40&&a%100!=0)){
cout<<"29";
}
else{
cout<<"28";
}
}
else if(b4||b6||b9||b==11){
cout<<"30";
}
else{
cout<<"31";
}
return 0;
}