010Valid Palindrome

def isPalindrome(s: str) -> bool:
    l, r = 0, len(s) - 1
    while l < r:
        while l < r and not s[l].isalnum(): l += 1
        while l < r and not s[r].isalnum(): r -= 1
        if s[l].lower() != s[r].lower(): return False
        l, r = l + 1, r - 1
    return True

public boolean isPalindrome(String s) {
    int l = 0, r = s.length() - 1;
    while (l < r) {
        while (l < r && !Character.isLetterOrDigit(s.charAt(l))) l++;
        while (l < r && !Character.isLetterOrDigit(s.charAt(r))) r--;
        if (Character.toLowerCase(s.charAt(l)) != Character.toLowerCase(s.charAt(r))) return false;
        l++; r--;
    }
    return true;
}

fun isPalindrome(s: String): Boolean {
    var l = 0; var r = s.length - 1
    while (l < r) {
        while (l < r && !s[l].isLetterOrDigit()) l++
        while (l < r && !s[r].isLetterOrDigit()) r--
        if (s[l].lowercaseChar() != s[r].lowercaseChar()) return false
        l++; r--
    }
    return true
}

bool isPalindrome(string s) {
    int l = 0, r = s.size() - 1;
    while (l < r) {
        while (l < r && !isalnum(s[l])) l++;
        while (l < r && !isalnum(s[r])) r--;
        if (tolower(s[l]) != tolower(s[r])) return false;
        l++; r--;
    }
    return true;
}

#include <ctype.h>
bool isPalindrome(char* s) {
    int l = 0, r = strlen(s) - 1;
    while (l < r) {
        while (l < r && !isalnum(s[l])) l++;
        while (l < r && !isalnum(s[r])) r--;
        if (tolower(s[l]) != tolower(s[r])) return false;
        l++; r--;
    }
    return true;
}