--- title: '15. 3Sum' description: 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 sidebar: label: '3Sum' badge: 'Medium' --- Two Pointers ::::warning 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` - `-10^5 <= nums[i] <= 10^5` ## Solution ```js /** * @param {number[]} nums * @return {number[][]} */ var threeSum = function(nums) { }; ```