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