Can Windows 8.1 RT join a domain

Question

I wrote the following to check if text is palindrome, I run it on leetcode and I am getting errors:

class Solution {
public:
    bool isPalindrome(string s) {
        int l=0,r=s.length()-1;
        while(l<r)
        {
            while (!isalpha(s[r]))
            {
                --r;
            }
            while (!isalpha(s[l]))
            {
                ++l;
            }
            if (tolower(s[r])!=tolower(s[l]))
                return false;
            --r;
            ++l;
        }
        return true;
    }
};

Line 1061: Char 9: runtime error: addition of unsigned offset to 0x7ffc7cc10880 overflowed to 0x7ffc7cc1087f (basic_string.h) SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior /usr/bin/../lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/basic_string.h:1070:9

what's the problem with my code?

Solution 1

No, according to the FAQ for Windows 8.1 RT, under the question "What's the difference between Windows 8.1 RT and Windows 8.1?":

Some features aren't included in Windows RT 8.1:

• Windows Media Player

• Windows Media Center

• HomeGroup creation (you can join an existing HomeGroup but you can't create a new one)

• The ability to connect to your Windows RT 8.1 PC from another PC using Remote Desktop

• Domain join

Solution 2

The Windows RT FAQ clearly states that joining a domain is not available in Windows RT 8.1.

Comments

[Thomas Sablik]

You're going out of bounds here: while (!isalpha(s[r])) and here while (!isalpha(s[l])). You should add some checks like while (l < s.length() && !isalpha(s[l]))

[Jarod42]

Input such as "" or "..." would be problematic.

[Ido]

As the runtime error declared, you are going to reach out of the string's limits. You should check that you are not going to pass those limits in each of your while loops.

[Admin]

but the checks will make the solution not valid if input was ","

[Thomas Sablik]

@calc But without the checks your code causes undefined behavior. What value do you expect from s[-1] or s[s.length() + 2]? That's exactly the problem in your code for input like s = "123", s = "" or s = ",". You're going out of bounds because you don't check the bounds. Is "," a palindrome or not?