409. Longest Palindrome

 1 static int wing=[]()
 2 {
 3     std::ios::sync_with_stdio(false);
 4     cin.tie(NULL);
 5     return 0;
 6 }();
 7 
 8 class Solution 
 9 {
10 public:
11     int longestPalindrome(string s) 
12     {
13         vector<int> vi(256,0);
14         for(char c:s)
15             vi[c]++;
16         int count=0;
17         int sub=0;
18         for(int i:vi)
19         {
20             if(i%2==0)
21                 count+=i;
22             else
23             {
24                 if(i>2)
25                     count+=(i-1);
26                 sub=1;
27             }
28         }
29             
30         return count+sub;
31     }
32 };