Question 1 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] Output: 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] Constraints: 2 <= nums.length <= 10 4 -10 9 <= nums[i] <= 10 9 -10 9 <= target <= 10 9 Only one valid answer exists. Follow-up: Can you come up with an algorithm that is less than O(n 2 ) time complexity? ******************************** Time Complexity (O(n^2)) ******************************** => Coding vector<int> twoSum(vector<int>& nums, int target) { vector<int> twoSum;