Question

I have a prototype restriction of bool pal(char str[], int length) and I need to test whether a string the user entered is a palindrome or not. The code I have is:

bool pal(char str[], int length)
{
    if(*str == str[length - 1])
    {
        pal(str+1, length-1);
    }
    else
    {
        return false
    }
    return true;
}

but it seems to only be testing if the first character is the same as the last character. I think this is because my array (start point) isn’t incrementing but I’m not sure why.

Answer 1

I suppose it’s probably due to some deep-seated aversion to if statements, but if it were up to me, I think I’d write the code something like this:

bool pal(char *str, size_t len) { 
    return len <2 || (str[0] == str[len-1] && pal(str+1, len-2));
}