#include<iostream> // cin\cout\endl using namespace std; int main(){ int n; cin>>n; switch(n){ case 1: case 3: case 5: case 7: case 8: case 10: case 12: cout<<31<<endl;break; case 2: cout<<29<<endl;break; case 4: case 6: case 9: case 11: cout<<30<<endl;break; default: cout<<"Invalid."<<endl;break; } return 0; }