LEETCODE--Longest Palindrome

最新推荐文章于 2022-08-02 07:23:38 发布

prettysky123

最新推荐文章于 2022-08-02 07:23:38 发布

阅读量171

点赞数

CC 4.0 BY-SA版权

分类专栏： leetcode

本文链接：https://blog.youkuaiyun.com/prettysky123/article/details/54882495

leetcode 专栏收录该内容

137 篇文章

订阅专栏

本文介绍了一种算法，该算法接收一个包含大小写字母的字符串，并找出能构建的最长回文子串的长度。案例研究中使用了abccccdd作为输入字符串，输出结果为7，解释了一个可能的最长回文子串dccaccd。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

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.

class Solution {
public:
    int longestPalindrome(string s) {
        int letters[52] = {0};
        for(int i = 0; i < s.length(); i++){
            if((s[i] - 'Z') > 0){
                letters[26 + (s[i] - 'a')]++; 
            }else{
                letters[s[i] - 'A']++;
            }
        }
        int odd = 0;
        int sum = 0;
        for(int j = 0; j < 52; j++){
            if(letters[j] % 2 != 0){
                odd = 1;
                sum += (letters[j] - 1);
            }else{
                sum += letters[j];
            }
        }
        if(odd == 1)
            return sum + 1;
        else
            return sum;
    }
};