#include <iostream> using namespace std; int main(){ int a,b; cin>>a; if(a<=7){ b=a%2; if(b=1){ cout<<"31"; }else if(a!=2){ cout<<"30"; }else{ cout<<"29"; } }else if(a<=12){ b=a%2; if(b=1){ cout<<"31"; }else if(a!=2){ cout<<"30"; }else{ cout<<"Invalid."; } }