single-number

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Algorithms

Given a non-empty&nbsp;array of integers <code>nums</code>, every element appears twice except for one. Find that single one.

You must&nbsp;implement a solution with a linear runtime complexity and use&nbsp;only constant&nbsp;extra space.

&nbsp;
Example 1:

<div class="example-block">
Input: nums = [2,2,1]

Output: 1
</div>

Example 2:

<div class="example-block">
Input: nums = [4,1,2,1,2]

Output: 4
</div>

Example 3:

<div class="example-block">
Input: nums = [1]

Output: 1
</div>

&nbsp;
Constraints:

<ul>
	<li><code>1 &lt;= nums.length &lt;= 3 * 104</code></li>
	<li><code>-3 * 104 &lt;= nums[i] &lt;= 3 * 104</code></li>
	<li>Each element in the array appears twice except for one element which appears only once.</li>
</ul>

singleNumber

Single Number

Single Number II

single-number-ii

只出现一次的数字 II

Single Number III

single-number-iii

只出现一次的数字 III

Missing Number

missing-number

丢失的数字

Find the Duplicate Number

find-the-duplicate-number

寻找重复数

Find the Difference

find-the-difference

找不同

Find the XOR of Numbers Which Appear Twice

find-the-xor-of-numbers-which-appear-twice

求出出现两次数字的 XOR 值

Bit Manipulation

Array

给你一个 非空 整数数组 <code>nums</code> ，除了某个元素只出现一次以外，其余每个元素均出现两次。找出那个只出现了一次的元素。

你必须设计并实现线性时间复杂度的算法来解决此问题，且该算法只使用常量额外空间。

<div class="original__bRMd">
<div>
&nbsp;

示例 1 ：

<div class="example-block">
输入：nums = [2,2,1]

输出：1
</div>

示例 2 ：

<div class="example-block">
输入：nums = [4,1,2,1,2]

输出：4
</div>

示例 3 ：

<div class="example-block">
输入：nums = [1]

输出：1
</div>

&nbsp;

提示：

<ul>
	<li><code>1 &lt;= nums.length &lt;= 3 * 104</code></li>
	<li><code>-3 * 104 &lt;= nums[i] &lt;= 3 * 104</code></li>
	<li>除了某个元素只出现一次以外，其余每个元素均出现两次。</li>
</ul>
</div>
</div>