Daily Challenge

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Monday, July 6, 2026

Two Sum

EasyArrays / Hashing

Given an array of integers `nums` and an integer `target`, return the indices of the two numbers that add up to `target`. Each input has exactly one solution, and you may not use the same element twice.

Input: nums = [2,7,11,15], target = 9
Output: [0,1]
// 2 + 7 = 9
Input: nums = [3,2,4], target = 6
Output: [1,2]
Constraints
  • 2 ≤ nums.length ≤ 10⁴
  • Exactly one valid answer exists
Your solution (scratchpad)