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
class Solution: def singleNumber(self, nums): """ :type nums: List[int] :rtype: int """ nums.sort() n=len(nums) i=0 while i!=n: if i==n-1 or nums[i]!=nums[i+1]: return nums[i] i+=2