Leetcode 1. Two Sum

Input: nums = [2,7,11,15], target = 9
Output: [0,1]
Output: Because nums[0] + nums[1] == 9, we return [0, 1].
Input: nums = [3,2,4], target = 6
Output: [1,2]
Input: nums = [3,3], target = 6
Output: [0,1]
  • 2 <= nums.length <= 103
  • -109 <= nums[i] <= 109
  • -109 <= target <= 109
  • Only one valid answer exists.
  1. create two loop to find the target
  1. using hashmap to note every target index
  2. TC: O(n)

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Gary Chiang

Gary Chiang

CS new grad, 6 years experience related to supply chain management. Located in Bay area