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MockQ12:41
Problem

1. Two Sum

Easy

Given an array of integers nums and an integer target, return 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.

Example 1:

Input: nums = [2,7,11,15], target = 9

Output: [0,1]

Because nums[0] + nums[1] == 9, we return [0, 1].

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 ≤ nums.length ≤ 10⁴
  • -10⁹ ≤ nums[i] ≤ 10⁹
  • -10⁹ ≤ target ≤ 10⁹
  • Only one valid answer exists.
Python
Loading editor…
MockQ
MMark
Scratchpad

need = target - n
seen before? return both
O(n) time, O(n) space

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mockq.io/interview/two-sum
MockQ12:41
Problem

1. Two Sum

Easy

Given an array of integers nums and an integer target, return 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.

Example 1:

Input: nums = [2,7,11,15], target = 9

Output: [0,1]

Because nums[0] + nums[1] == 9, we return [0, 1].

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 ≤ nums.length ≤ 10⁴
  • -10⁹ ≤ nums[i] ≤ 10⁹
  • -10⁹ ≤ target ≤ 10⁹
  • Only one valid answer exists.
Python
Loading editor…
MockQ
MMark
Scratchpad

need = target - n
seen before? return both
O(n) time, O(n) space

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