#include <stdio.h>

int main(void){
  //
  // declare and intialize working storage
  //
  int marks;

  //
  //prompt for grade
  //
  printf("Enter your marks :");
  scanf("&d", &marks);

  if(marks <= 100 && marks >=90){
     printf("You got an A");
  }
  else if(marks <= 89 && marks >=80){
    printf("You got a B");
  }
  else if(marks <= 79 && marks >=70){
    printf("You got a C");
  }
  else if(marks <= 69 && marks >= 50){
    printf("You got a D");
  }
  else{
    printf("error");
  }



}