# Leetcode: Longest Palindrome

Longest Palindrome Similar Problems:

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.
```

Github: code.dennyzhang.com

Credits To: leetcode.com

Leave me comments, if you have better ways to solve.

```## Blog link: https://code.dennyzhang.com/longest-palindrome
## Basic Ideas:
## Complexity:
class Solution(object):
def longestPalindrome(self, s):
"""
:type s: str
:rtype: int
"""
## Idea: Use a map and count characters
## Complexity:
count_map = {}
for ch in s:
if count_map.has_key(ch) is False:
count_map[ch] = 1
else:
count_map[ch] += 1
has_odd = False
res = 0
for ch in count_map.keys():
if count_map[ch] % 2 == 0:
res += count_map[ch]
else:
has_odd = True
res += count_map[ch] - 1
return res+1 if has_odd else res
```

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