C program to calculate student grades.

#include<stdio.h>
#include<conio.h>
void main()
{
 clrscr();
 int mark[5], i;
 float sum=0,avg;
 printf("Enter marks obtained in 5 subjects :");
 for(i=0; i<5; i++)
 {
  scanf("%d",&mark[i]);
  sum=sum+mark[i];
 }
 avg=sum/5;
 printf("Your Grade is ");
 if(avg>80)
 {
  printf("A");
 }
 else if(avg>60 && avg<=80)
 {
  printf("B");
 }
 else if(avg>40 && avg<=60)
 {
  printf("C");
 }
 else
 {
  printf("D");
 }
 getch();
}