#1 - Two Sum

Easy • View on LeetCode • View on GitHub

Problem Description

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.

You can return the answer in any order.

Solution

/**
 * @param {number[]} nums
 * @param {number} target
 * @return {number[]}
 */
var twoSum = function(nums, target) {
  const map = new Map();

  for (let i = 0; i < nums.length; i++) {
    const diff = target - nums[i];

    if (map.has(diff)) {
      return [map.get(diff), i];
    }

    map.set(nums[i], i);
  }
};