Two Sum

Arrays & Hashing, problem 3 of 9

Two Sum

Easy

LC #1

hash mapcomplement lookup

Not attempted yet

Given an integer list nums and an integer target, return the indices of the two numbers that add up to target.

Exactly one pair works, and you may not use the same element twice. Return the two indices in any order.

Example 1

Input: nums = [2, 7, 11, 15], target = 9
Output: [0, 1]
nums[0] + nums[1] = 2 + 7 = 9

Example 2

Input: nums = [3, 2, 4], target = 6
Output: [1, 2]

Example 3

Input: nums = [3, 3], target = 6
Output: [0, 1]

Constraints

  • 2 ≤ len(nums) ≤ 10^5
  • -10^9 ≤ nums[i], target ≤ 10^9
  • Exactly one valid answer exists

Python

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Test results

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