#include<bits/stdc++.h>
using namespace std;
int main()
{
	int a,b,n;
    cin>>a>>b;
    if(b==1||b==3||b==5||b==7||b==8||b==10||b==12)
    {
        cout<<"31";
    }
    else if(b==2)
    {
        if(a%4==0 && a%100!=0 || a%400==0)
        {
            cout<<"29";
        }
        else cout<<"28";
    }
    else cout<<"30";
	return 0;
}

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

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

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