CodeEasy v0.1

Single Number

Easy Subject: Bit Manipulation
Time Complexity
O(N)
Space Complexity
O(1)

Problem Description

Given a non-empty array of integers nums, every element appears twice except for one. Find that single one. You must implement a solution with linear runtime complexity and constant space.

Optimal Solution

Python 
def singleNumber(nums):
    xor = 0
    for num in nums:
        xor ^= num
    return xor