136. Single Number
https://leetcode.com/problems/single-number/
Intuition
XOR of number with itself is zero
XOR of number with 0 is itself
XOR all array elements, all duplicates with result in 0, and XOR with unique number will be unique answer
---
Related problems
137-single-number-ii
---
Given a non-empty array of integers, every element appears twice except for one. Find that single one.
Note:
Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory?
Example 1:
Input: [2,2,1] Output: 1
Example 2:
Input: [4,1,2,1,2] Output: 4---
Intuition
XOR of number with itself is zero
XOR of number with 0 is itself
XOR all array elements, all duplicates with result in 0, and XOR with unique number will be unique answer
---
Related problems
137-single-number-ii
---
