C Program to find Reverse Case for Any Alphabet

C Program to Find Reverse Case for any Alphabet

This c program uses toupper and tolower predefined function from ctype header to return the corresponding reverse case for any alphabet.

#include<stdio.h>                                                           
#include<ctype.h>                                                            
                                                                                
void main()                                                                     
{                                                                               
    char alph,rev;                                                              
    printf("Enter an alphabet : ");                                             
    scanf("%c", &alph);                                                         
                                                                                
    if(islower(alph))                                                           
      rev = toupper(alph);                                                      
    else                                                                        
      rev = tolower(alph);                                                      
    printf("Reverse case of %c is : %c\n", alph, rev);                        
                                                                                
}                                                                 
                                                                                  

$ cc reverse_case.c
$ ./a.out 
Enter an alphabet : W
Reverse case of W is : w

$ ./a.out 
Enter an alphabet : r
Reverse case of r is : R