标签:leetcode
Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases.
For example,
"A man, a plan, a canal: Panama"
is a palindrome.
"race a car"
is not a palindrome.
Note:
Have you consider that the string might be empty? This is a good question to ask during an interview.
For the purpose of this problem, we define empty string as valid palindrome.
class Solution { public: bool isPalindrome(string s) { int n = s.length(); if(n==0 || n==1) return true; int i=0,j=n-1; while(i<=j) { if(s[i] < '0' || (s[i] >'9' && s[i]<'A') || (s[i]>'Z' && s[i] <'a') || s[i]>'z') { i++; continue; } if(s[j]<'0' || (s[j]> '9' && s[j]<'A') || (s[j]>'Z' && s[j] <'a') || s[j]>'z') { j--; continue; } if(s[i]==s[j] || abs(s[i] - s[j])==32) { i++; j--; } else return false; } return true; } };
标签:leetcode
原文地址:http://blog.csdn.net/shaya118/article/details/42721417