The following example will check for a palindrom in C. You know one of thoose words spelt the same forwards as backwards. The smart part of this program is the edge case where you have an odd number of letters in the string. Well actually this can simply be ignored since there is no point in comparing the middle charecter to its self.

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

int try(char *str) {
    int len = strlen(str);
    int i;
    for(i =0;i<len/2;i++)
        if (str[i] != str[len - 1 - i])
            return 0;
    return 1;
}

int main(int argc, char**argv) {
    char *s1 = "ffoof";
    char *s2 = "foof";
    char *s3 = "fooof";

    if (try(s1))
        printf("%s\n", s1);

    if (try(s2))
        printf("%s\n", s2);

    if (try(s3))
        printf("%s\n", s3);

    return 0;
}