Longest Substring Without Repeating Characters

• Valid Palindrome ```python import re

class Solution: def isPalindrome(self, s: str) -> bool: s = re.sub(r’[^a-zA-Z0-9]’, ‘’, s).lower() #print(s)

    for i in range(len(s) // 2):
        j = len(s) - i - 1
        if s[i] != s[j]:
            #print(f"s[{i}]={s[i]} != s[{j}]={s[j]}")
            return False
    
    return True ```

Another solution:

class Solution:
    def isPalindrome(self, s: str) -> bool:
        s1 = ''.join([i.lower() for i in s if i.isalnum()])
        #print(s1)
        s2 = s1[::-1]
        #print(s2)
        return s1==s2

Other

• Engineering Skills