Given an integer array nums and an integer target, return the indices of the two distinct elements whose sum equals target. Assume exactly one valid answer exists, and the same element cannot be used 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