leetcode 389. Find the Difference

目录

一、问题描述

二、代码实现

1、桶排序

2、异或法

3、求和法

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https://leetcode.com/problems/find-the-difference/

给定两个字符串，其中一个字符串是在另一个字符串的任意位置添加一个字母得到的，求这个字母

 

一、问题描述

测试用例：

Example:

Input:
s = "abcd"
t = "abcde"

Output:
e

Explanation:
'e' is the letter that was added.

字符串的元素均为小写字母

 

二、代码实现

1、桶排序

class Solution {
    
    //数组
    public char findTheDifference2(String s, String t) {
        int[] count = new int[26];  //HashMap, Array, Bits
        for (int i=0; i map = new HashMap<>();
        for (int i=0; i

2、异或法

class Solution {

    public char findTheDifference3(String s, String t) {
        char ret = t.charAt(t.length()-1);
        
        for (int i=0; i

3、求和法

class Solution {
    
    public char findTheDifference4(String s, String t) {
        int sum = t.charAt(t.length()-1);
        
        for (int i=0; i

 

参考：

https://leetcode.com/problems/find-the-difference/discuss/86850/Simple-JAVA-8ms-solution-4-lines

https://leetcode.com/problems/find-the-difference/discuss/86913/JavaC%2B%2B-1-liner

https://leetcode.com/problems/find-the-difference/discuss/87049/Simple-Java-Solution-Bit-Manipulation-5ms

https://leetcode.com/problems/find-the-difference/discuss/87095/Two-Java-Solutions-using-XOR-Sum

https://leetcode.com/problems/find-the-difference/discuss/86825/Java-solution-using-bit-manipulation

https://leetcode.com/problems/find-the-difference/discuss/87114/simple-cpp-solution

https://leetcode.com/problems/find-the-difference/discuss/86844/Java-Solution-using-array%3A-6ms

https://leetcode.com/problems/find-the-difference/discuss/87051/easy-Java-O(n)-solution-using-map