# include<iostream> # include<cstdio> # include<iomanip> # include<cmath> using namespace std; int main(){ int a; cin>>a; if(a>=90){ cout<<"A"; } else if(a>=80){ cout<<"B"; } else if(a>=70){ cout<<"C"; } else if(a>=60){ cout<<"D"; } else{ cout<<"E"; } return 0; }