Given an integer array nums, return all the triplets [nums[i], nums[j], nums[k]] such that i != j, i != k, and j != k, and nums[i] + nums[j] + nums[k] == 0.Notice that the solution set must not contain duplicate triplets. Example 1:Input: nums = [-1,0,1,2,-1,-4]Output: [[-1,-1,2],[-1,0,1]]Explanation: nums[0] + nums[1] + nums[2] = (-1) + 0 + 1 = 0.nums[1] + nums[2] + nums[4] = 0 + 1 + (-1) = 0.nums[0] + nums[3] + nums[4] = (-1) + 2 + (-1) = 0.The distinct triplets are [-1,0,1] and [-1,-1,2].Notice that the order of the output and the order of the triplets does not matter.Example 2:Input: nums = [0,1,1]Output: []Explanation: The only possible triplet does not sum up to 0.Example 3:Input: nums = [0,0,0]Output: [[0,0,0]]Explanation: The only possible triplet sums up to 0. Constraints:3 <= nums.length <= 3000-105 <= nums[i] <= 105

Given an array nums of n integers, return an array of all the unique quadruplets [nums[a], nums[b], nums[c], nums[d]] such that:0 <= a, b, c, d < na, b, c, and d are distinct.nums[a] + nums[b] + nums[c] + nums[d] == targetYou may return the answer in any order. Example 1:Input: nums = [1,0,-1,0,-2,2], target = 0Output: [[-2,-1,1,2],[-2,0,0,2],[-1,0,0,1]]Example 2:Input: nums = [2,2,2,2,2], target = 8Output: [[2,2,2,2]] Constraints:1 <= nums.length <= 200-109 <= nums[i] <= 109-109 <= target <= 109

You are given an integer array nums of size n and a positive integer k.Divide the array into one or more arrays of size 3 satisfying the following conditions:Each element of nums should be in exactly one array.The difference between any two elements in one array is less than or equal to k.Return a 2D array containing all the arrays. If it is impossible to satisfy the conditions, return an empty array. And if there are multiple answers, return any of them.

442. Find All Duplicates in an ArrayMediumTopicsCompaniesGiven an integer array nums of length n where all the integers of nums are in the range [1, n] and each integer appears once or twice, return an array of all the integers that appears twice.You must write an algorithm that runs in O(n) time and uses only constant extra space. Example 1:Input: nums = [4,3,2,7,8,2,3,1]Output: [2,3]Example 2:Input: nums = [1,1,2]Output: [1]Example 3:Input: nums = [1]Output: [] Constraints:n == nums.length1 <= n <= 1051 <= nums[i] <= nEach element in nums appears once or twice.

Minimum Sum of Mountain Triplets IIMy SubmissionsBack to ContestUser Accepted:8130User Tried:10428Total Accepted:8348Total Submissions:17555Difficulty:MediumYou are given a 0-indexed array nums of integers.A triplet of indices (i, j, k) is a mountain if:i < j < knums[i] < nums[j] and nums[k] < nums[j]Return the minimum possible sum of a mountain triplet of nums. If no such triplet exists, return -1. Example 1:Input: nums = [8,6,1,5,3]Output: 9Explanation: Triplet (2, 3, 4) is a mountain triplet of sum 9 since: - 2 < 3 < 4- nums[2] < nums[3] and nums[4] < nums[3]And the sum of this triplet is nums[2] + nums[3] + nums[4] = 9. It can be shown that there are no mountain triplets with a sum of less than 9.Example 2:Input: nums = [5,4,8,7,10,2]Output: 13Explanation: Triplet (1, 3, 5) is a mountain triplet of sum 13 since: - 1 < 3 < 5- nums[1] < nums[3] and nums[5] < nums[3]And the sum of this triplet is nums[1] + nums[3] + nums[5] = 13. It can be shown that there are no mountain triplets with a sum of less than 13.Example 3:Input: nums = [6,5,4,3,4,5]Output: -1Explanation: It can be shown that there are no mountain triplets in nums. Constraints:3 <= nums.length <= 1051 <= nums[i] <= 108

Given an integer array nums of length n where all the integers of nums are in the range [1, n] and each integer appears once or twice, return an array of all the integers that appears twice.You must write an algorithm that runs in O(n) time and uses only constant extra space. Example 1:Input: nums = [4,3,2,7,8,2,3,1]Output: [2,3]Example 2:Input: nums = [1,1,2]Output: [1]Example 3:Input: nums = [1]Output: [] Constraints: