Two Sum.js

// Write a function that takes an array of numbers (integers for the tests) and a target number. It should find two different items in the array that, when added together, give the target value. The indices of these items should then be returned in a tuple / list (depending on your language) like so: (index1, index2).

// For the purposes of this kata, some tests may have multiple answers; any valid solutions will be accepted.

// The input will always be valid (numbers will be an array of length 2 or greater, and all of the items will be numbers; target will always be the sum of two different items from that array).

// Based on: https://leetcode.com/problems/two-sum/

// twoSum([1, 2, 3], 4) // returns [0, 2] or [2, 0]


function twoSum(nums, target) {
    const numMap = {};
    for (let i = 0; i < nums.length; i++) {
        const complement = target - nums[i];
        if (complement in numMap) {
            return [numMap[complement], i];
        }
        numMap[nums[i]] = i;
    }
}