C Program to Check Whether Character is Lowercase or Not

How to check whether the given character is a lowercase alphabet or not using islower built-in function and not using islower function. In C Programming, islower is a built-in function, used to check whether the character is a lowercase alphabet or not.

C Program to Check Whether Character is Lowercase or Not using islower function

This C program allows the user to enter any character and check whether the character is a lowercase alphabet or not

#include <stdio.h>
#include <ctype.h>

int main()
{
  char Ch;
 
  printf("\n Please Enter any alphabet\n");
  scanf("%c", &Ch);

  if ( islower(Ch) )
   {  
     printf ("\n Entered character is lowercase alphabet");
   }
  else
   {
     printf("\n Entered character is Not lowercase alphabet");
   }  
}

OUTPUT

ANALYSIS

In this C Program to Check Whether Character is Lowercase, we used the If Statement,

if (islower(Ch))

If the above condition islower(Ch) is TRUE, the given character is a lowercase alphabet. So, it will print the below statement

printf ("\n Entered character is lowercase alphabet");

If the above condition islower(Ch) is FALSE, the given character is not lowercase alphabet. So, it will print the below statement

printf ("\n Entered character is Not lowercase alphabet");

Program to Check Whether Character is Lowercase or Not without using islower function

This program allows the user to enter any character and check whether the character is a lowercase alphabet or not without using islower function.

#include <stdio.h>

int main()
{
  char Ch;

  printf("\n Please Enter any alphabet\n");
  scanf("%c", &Ch);

  if (Ch >= 'a' && Ch <= 'z')
   {  
     printf ( "\nEntered character is lowercase alphabet") ;
   }
  else
   {
     printf("\nEntered character is Not lowercase alphabet");
   }  
}

OUTPUT

Let us check with a false value

ANALYSIS

Within this C Program for Lowercase,  If you look at the If Statement

 if (Ch >= 'a' && Ch <= 'z')

As we all know, all the lowercase characters are between a and z. So, the above if condition will check whether the given character is between a and z.

If the above condition (Ch >= ‘a’ && Ch <= ‘z’) is TRUE, the given character is a lowercase alphabet. So, it will print the below statement

printf ("\n Entered character is lowercase alphabet");

If the above condition (Ch >= ‘a’ && Ch <= ‘z’) is FALSE, the given character is not lowercase alphabet. So, it will print the below printf statement

printf ("\n Entered character is Not lowercase alphabet");

C Program to Check Whether Character is Lowercase or Not using ASCII Values

This program checks whether the character is a lowercase alphabet or not without using islower function.

#include <stdio.h>

int main()
{
  char Ch;
  
  printf("\n Please Enter any character\n");
  scanf("%c", &Ch);

  if (Ch >= 97 && Ch <= 122)
   {  
     printf ( "\nEntered character is lowercase alphabet") ;
   }
  else
   {
     printf("\nEntered character is Not lowercase alphabet");
   }  
}

OUTPUT

ANALYSIS

In this c lowercase program, If you look at the If Statement

if (Ch >= 97 && Ch <= 122)

If the above condition if (Ch >= 97 && Ch <= 122) is TRUE, the given character is a lowercase alphabet. So, it will print the below printf statement

printf ("\n Entered character is lowercase alphabet");

If the above condition if (Ch >= 97 && Ch <= 122) is FALSE, the given character is not lowercase alphabet. So, it will print the below statement

printf ("\n Entered character is Not lowercase alphabet");