leetCode刷题(找到最长的回文字符串)

Given a string, find the length of the longest substring without repeating characters.

Examples:

Given "abcabcbb", the answer is "abc", which the length is 3.

Given "bbbbb", the answer is "b", with the length of 1.

Given "pwwkew", the answer is "wke", with the length of 3. Note that the answer must be a substring, "pwke" is a subsequenceand not a substring.

/**
 * @param {string} s
 * @return {string}
 */
var longestPalindrome = function(s) {
  var maxLength="";
  var maxPalindrome="";
  for(index=0;index<s.length;index++){
      var strOdd=getPalindromeLength(index,index,s);
      var strEven=getPalindromeLength(index,index+1,s);
      var strOddLength=strOdd.length;
      var strEvenLength=strEven.length;
      if(maxLength<strOddLength){
          maxLength=strOddLength;
          maxPalindrome=strOdd;
      }
      if(maxLength<strEvenLength){
          maxLength=strEvenLength;
          maxPalindrome=strEven;
      }
  }
  function getPalindromeLength(start,end,Palindrome){
      while((start>=0)&&(end<Palindrome.length)&&(Palindrome[start]==Palindrome[end])){
            start--;
            end++;
      }
      return Palindrome.substring(start+1,end);
  }
  return maxPalindrome
};