Leetcode 125. Valid Palindrome
阿新 • • 發佈:2018-12-13
Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases.
Note: For the purpose of this problem, we define empty string as valid palindrome.
Example 1:
Input: "A man, a plan, a canal: Panama" Output: true
Example 2:
Input: "race a car" Output:false
Answer:
class Solution(object): def isPalindrome(self, s): """ :type s: str :rtype: bool """ l=len(s) i=0 j=l-1 while i<=j: ic=s[i] jc=s[j] if not ic.isalnum(): i+=1 continue if not jc.isalnum(): j-=1 continue if ic.lower()!=jc.lower(): return False i+=1 j-=1 return True