In this program we are going to see whether a user given character is alphabet or not. To determine the type of character, we have to check it’s ASCII value range.

See also: Find ASCII value of a character

Logic

To check if it is a alphabet or not we only need to check its ASCII value range. If it is a alphabet then it’s ASCII value range should be within 65 (A) – 90 (Z) or 97 (a) – 122 (z).

Program

AlphabetOrNot.CCopy
#include <stdio.h>

int main() {

    char c;
        
    printf("Enter any character : ");
    scanf("%c", &c);
    
    if((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {

        printf("\n%c is ALPHABET.\n", c);

    } else {

        printf("\n%c is NOT ALPHABET.\n", c);

    }

    return 0;
}
Try It

Output

Enter any character : x
x is ALPHABET.