#include<iostream> using namespace std; int main(){ int a; cin>>a; switch(a) { 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; case 2: cout<<29; break; default: cout<<"Invalid."<<endl; } return 0; }