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