Thread: No Output

hi , my probleam cannot display output.. please comment so that i can fix the error

Code:

#include <stdio.h>
  int main()
{
    int marks;
    printf("Enter Mark :");
    scanf("%d", &marks);
    switch (marks)
    {
    
    case 1:    if( marks > 80 && marks < 100)
            printf( " Grad A");
            break;
    case 2: if(marks > 70 && marks < 79  )
            printf( " Grad B");
            break;
    case 3: if( marks > 60 && marks < 69)
            printf( " Grad C");
            break;
    case 4: if( marks  >50 && marks < 59)
            printf( " Grad D");
            break;
    case 5: if( marks > 40 && marks < 49)
            printf( " Grad D");
            break;
    default: if( marks < 39)
            printf( " Grade F");
    
    }
    
}

tq...salem...it work.
i delete all switch/case and replace with if and else if. Tq again