#include<bits/stdc++.h> using namespace std; int main(){ int n; cin>>n; if(n==1||n==3||n==5||n==7||n==8||n==10||n==12) cout<<31<<endl; else if(n==4||n==6||n==9||n==11) cout<<30<<endl; else if(n==2) cout<<29<<endl; else cout<<"Invalid.\n"; return 0; }