#include<iostream>
using  namespace std;
int main(){
	int y,m;
	cin>>y>>m;
	if(m==1) cout<<31;
	if(m==2){
	    if(y%4==0 and y%100!=0 or y%400==0)
		cout<<29;
	else
		cout<<28;
    }
    if(m==3) cout<<31;
    if(m==4) cout<<30;
    if(m==5) cout<<31;
    if(m==6) cout<<30;
    if(m==7) cout<<31;
    if(m==8) cout<<31;
    if(m==9) cout<<30;
    if(m==10) cout<<31;
    if(m==11) cout<<30;
    if(m==12) cout<<31;
	return 0;
}

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#include <bits/stdc++.h> using namespace std; int main() { int y,m,d; cin>>y>>m; if(m1 or m3 or m5 or m7 or m8 or m10 or m12) { d=31; } else if(m4 or m6 or m9 or m11) { d=30; } else if(m2) { if(y%40&&y%100!=0||y%4000) { d=29; } else { d=28; } } else { d=0; } cout<<d; return 0; }

#include <bits/stdc++.h> using namespace std; int main() { int y,m; cin>>y>>m; if(m2) if((y%40&&y%100!=0)||y%400==0)cout<<"29"; else cout<<"28"; switch(m) {case 1: case 3: case 5: case 7: case 8: case 10: case 12: cout<<"31";break; case 4: case 6: case 9: case 11:cout<<"30";break; }

return 0;

}

#include <bits/stdc++.h> using namespace std; int main() { int y,m; cin>>y>>m; if(m2) if((y%40&&y%100!=0)||y%400==0)cout<<"29"; else cout<<"28"; switch(m) {case 1: case 3: case 5: case 7: case 8: case 10: case 12: cout<<"31";break; case 4: case 6: case 9: case 11:cout<<"30";break; }

return 0;

}

#include using namespace std; int main(){ int y,m; cin>>y>>m; if(m1) cout<<31; if(m2){ if(y%40 and y%100!=0 or y%4000) cout<<29; else cout<<28; } if(m3) cout<<31; if(m4) cout<<30; if(m5) cout<<31; if(m6) cout<<30; if(m7) cout<<31; if(m8) cout<<31; if(m9) cout<<30; if(m10) cout<<31; if(m11) cout<<30; if(m12) cout<<31; return 0; }

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

   return 0; }