twoSum = (nums, target) => {
    const map = getMap(nums);       /* Time O(N) | Space O(N) */

    return getSum(nums, target, map)/* Time O(N) */
}
Hash Map - 2 Pass
Time O(N) | Space O(N)
https://leetcode.com/problems/two-sum/
@param {number[]} nums
@param {number} target
@return {number[]}