# 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. You can return the answer in any order. Example 1: Input: nums = [2,7,11,15], target = 9 Output: [0,1] Explanation: 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] # Solution: ```javascript var twoSum = function twoSum(nums, target) { let numObj = {}; for (let i = 0; i < nums.length; i++) { let neededNum = target - nums[i]; console.log(numObj); if (numObj[neededNum] !== undefined) { return [numObj[neededNum], i]; } numObj[nums[i]] = i; } } ``` # Explanation: 
 1. Store elements in nums in a new object.
  2. For the key-value pairs use each element and its index.
  3. While you're going through nums, find the difference between the target and the current element.
  4. If that difference is already saved as a key, return it's value (aka it's index in nums), and the current index.

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