by C:
int palindromeIndex(char* s) {

    int len=0, left=0, right=len-1, tempLeft=0, tempRight=len-1;
    if(s != NULL) {
        while(s[len]!='\0') len++;
        right=len-1;
        tempRight=len-1;

        // normal checking
        while(left<right && (s[left]==s[right])) {
            left++;
            right--;
        }
        if(left>=right) return -1;

        // try to skip left
        tempLeft = left++;
        tempRight = right;
        while(left<right &&(s[left]==s[right])) {
            left++;
            right--;
        }
        if(left>=right) return tempLeft;

        // try to skip right ,BUT need first to back to the old value
        left = tempLeft;
        right = tempRight-1;
        while(left<right && (s[left]==s[right])) {
            left++;
            right--;
        }
        if(left>=right) return tempRight;
        else
            return -1; // so no solution for this string

    } else {
        return -1;
    }


}