2014-10-20 11:23:39 +08:00
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// Source : https://oj.leetcode.com/problems/valid-palindrome/
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// Author : Hao Chen
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// Date : 2014-06-26
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2014-10-21 10:49:57 +08:00
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/**********************************************************************************
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*
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* Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases.
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*
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* For example,
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* "A man, a plan, a canal: Panama" is a palindrome.
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* "race a car" is not a palindrome.
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*
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* Note:
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* Have you consider that the string might be empty? This is a good question to ask during an interview.
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*
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* For the purpose of this problem, we define empty string as valid palindrome.
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*
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*
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**********************************************************************************/
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2014-10-20 11:23:39 +08:00
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class Solution {
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public:
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bool isPalindrome(string s) {
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s = removeNoise(s);
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for(int i=0; i<s.size()/2; i++){
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if (s[i]!= s[s.size()-i-1]){
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return false;
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}
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}
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return true;
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}
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string removeNoise(string& s){
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string d;
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for(int i=0; i<s.size(); i++){
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if(::isalpha(s[i]) || ::isdigit(s[i])){
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d.push_back(::tolower(s[i]));
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}
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}
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return d;
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}
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};
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