Single Number
Detailed guide and Python implementation for the 'Single Number' problem.
Problem Statement
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.
Write a function singleNumber(nums: List[int]) -> int.
- •1 <= len(nums) <= 3 * 10^4
- •-3 * 10^4 <= nums[i] <= 3 * 10^4
- •Each element in the array appears twice except for one element which appears only once
Examples
nums = [2,2,1]
1
The element 1 appears once.
nums = [4,1,2,1,2]
4
The element 4 appears once.
nums = [1]
1
The element 1 appears once.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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