// LEVEL 2.5
#include <iostream>
using namespace std;
int bal;
int main() {
cout<<"balı daxil edin: ";
cin>>bal;
if (bal>90){
cout<<"A";
}
else if (bal>80){
cout<<"B";
}
else if(bal>70){
cout<<"C" ;
}
else if(bal>60){
cout<<"D";
}
else if(bal>50){
cout<<"E";
}
else if(bal<=50){
cout<<"F";
}
return 0;
}
