Thread: Palindrome C program where capital letters dont matter

Hi guys,

Im working on a palindrome program and the internet has been quite helpfull, I have been able to write a program that almost works as I want it to work. The only thing I'm struggling with is that capital letters are not the same as normal letters in ASCII.
I would like my program to be able to mark both 'mum' and 'Mum' as a palindrome.
This is my code for now :

Code:

#include <stdio.h>
#include <string.h>


int main() {
    char palindroom[50];
    int lengte, i;
    int woord = 0;


    printf("Enter a string:\t");
    scanf("%s", palindroom);


    lengte = strlen(palindroom);


    for (i = 0; i < lengte; i++) {
        if (palindroom[i] != palindroom[lengte - i - 1]) {
            woord = 1;
            break;
        }
    }


    if (woord) {
        printf("%s is not a palindrome", palindroom);
    }
    else {
        printf("%s is a palindrome", palindroom);
    }
    getchar();
    return 0;
}

not all words are English as you can read, that's Dutch but I think you'll understand.

I would like my program to be able to mark both 'mum' and 'Mum' as a palindrome.

Then perhaps you should be comparing the characters using the same case using something like tolower() (from ctype.h).

Code:

 if (tolower(palindroom[i]) != tolower(palindroom[lengte - i - 1]))

And be careful that line has a buffer underflow error when lengte is less than 2.