【leetcode】409. Longest Palindrome【E】

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.

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还是不难的，看例子就知道了

能够成回文，除了中间的之外，每个字母都必须出现偶数次

中间的字母可以出现一次

所以，就对整个字符串每个字符计数，出现偶数次的直接加上

基数次的，保证全局只加一个1就行了

class Solution(object):
    def longestPalindrome(self, s):
        ss = set(s)
        #print ss
        res = 0
        for i in ss:
            tmp = s.count(i)
            if tmp % 2 == 0:
                res += tmp
            else:
                if tmp > 1:
                    res += (tmp - 1)
                    tmp = 1
                if res%2 == 0:
                    res += 1
        return res