Algo

Question 1

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 a linear runtime complexity and use only constant extra space.

Answer 1

Use XOR

class Solution:
    def singleNumber(self, nums: List[int]) -> int:

    res = nums[0]
    for i in range(1,len(nums)):

        res = res^nums[i]

    return res