Given an unsorted array of integers nums and an integer target, return the indices of the two distinct elements whose sum is target. Exactly one valid answer exists, and you may not use the same element twice.
nums = [2, 7, 11, 15], target = 9Output[0, 1]Why2 + 7 = 9nums = [3, 2, 4], target = 6Output[1, 2]Why2 + 4 = 6`2 <= len(nums) <= 10^5``-10^9 <= nums[i] <= 10^9``-10^9 <= target <= 10^9`Exactly one valid answer exists