Two Sum
Detailed guide and Python implementation for the 'Two Sum' problem.
Problem Statement
Given an array of integers nums and an integer target, return the indices of the two numbers such that they add up to target.
You may assume that each input would have exactly one solution, and you may not use the same element twice.
You can return the answer in any order.
Write a function twoSum(nums: List[int], target: int) -> List[int].
- •2 <= len(nums) <= 10^4
- •-10^9 <= nums[i] <= 10^9
- •-10^9 <= target <= 10^9
- •Only one valid answer exists
Examples
nums = [2, 7, 11, 15], target = 9
[0, 1]
nums[0] + nums[1] = 2 + 7 = 9, so we return [0, 1].
nums = [3, 2, 4], target = 6
[1, 2]
nums[1] + nums[2] = 2 + 4 = 6, so we return [1, 2].
nums = [3, 3], target = 6
[0, 1]
nums[0] + nums[1] = 3 + 3 = 6, so we return [0, 1].
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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