409.longest palindrome

1. Longest Palindrome Add to List
   Description Submission Solutions
   Total Accepted: 28693
   Total Submissions: 64338
   Difficulty: Easy
   Contributors: Admin
   Given a string which consists of lowercase or uppercase letters, find the length of the longest palindromes that can be built with those letters.

This is case sensitive, for example “Aa” is not considered a palindrome here.

Note:
Assume the length of given string will not exceed 1,010.

Example:

Input:
“abccccdd”

Output:
7

Explanation:
One longest palindrome that can be built is “dccaccd”, whose length is 7.

很简单得题目

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19

class Solution {
public:
    int (string s) {
        unordered_map<char,int> ma;
        for(int i=0;i<s.length();i++)
        ma[s[i]]++;
        unordered_map<char,int>::iterator it=ma.begin();
        int len=0;
        bool w=false;
        for(;it!=ma.end();it++)
        {len+=((it->second)/2);
         if(it->second%2==1)
         w=true;
        }
  return  w?(len*2+1):(len*2);
        
    }
};