#C_CODE: palindrome code in c using pointers.

/* Details: Palindrome code using pointer
 * Author : Vinod Sasidharan
 * Date   : Wednesday, March 16, 2011, 10.14 am
 * Remarks: Multiple words possible in input string due
 * to use of fgets.
 */

/* Include files */
#include <stdio.h>
#include <string.h>

/* Function prototype declaration */
unsigned char palindrome(char *s);

/* Function name: Palindrome
* Input : Pointer to a string
* Output : 8bit unsigned - 0/1
*/
unsigned char palindrome(char *s)
{
    char *s2 = s + strlen(s) - 1;

    /* Sanity check */
    if(!*s) return 0;

    while(*(s2--) == *(s++) && *s);
    return((unsigned char)(!*s && *(++s2) == *(--s)));
}

/* Main function */
int main()
{
    char buff[35];

    fputs("Input string: ",stdout);
    fgets(buff,sizeof(buff),stdin);
    fflush(stdin);

    /* To avoid the \n in the input string */
    *(buff + strlen(buff) - 1) = '\0';

    printf("Is the string %s palindrome: %s\n",buff,
    palindrome(buff)?"YES":"NO");
    getchar();
    return 0;
}

Tested on: Visual C++ 2008 Express Edition, Windows XP