#include<iostream> using namespace std; int main(){ int a; char b; cin>>a; if(a>=90){ b='A'; } else if(a>=70){ b='B'; } else if(a>=60){ b='C'; } else{ b='D'; } switch(b){ case 'A':cout<<"A";break; case 'B':cout<<"B";break; case 'C':cout<<"C";break; case 'D':cout<<"D";break; } }