Given an integer array nums, return all the triplets `[nums[i], nums[j], nums[k]]` such that `i != j`, `i != k`, `j != k`, and `nums[i] + nums[j] + nums[k] == 0`.
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]]
```
**Example 2:**
```
Input: nums = [0,0,0]
Output: [[0,0,0]]
```