Longest Palindrome
给一个字符串, 找出其中最长的回文, 返回它的长度.
public class Solution {
public int longestPalindrome(String s) {
if(s == null || s.length() == 0)
return 0;
Set<Character> set = new HashSet<Character>();
int count = 0;
for(int i = 0 ; i < s.length(); i++) {
if(set.contains(s.charAt(i))){
set.remove(s.charAt(i));
count++;
}
else{
set.add(s.charAt(i));
}
}
if(!set.isEmpty())
return count*2+1;
else
return count*2;
}
}