There is an integer array `nums` that consists of `n` unique elements, but you have forgotten it. However, you do remember every pair of adjacent elements in `nums`.

You are given a 2D integer array `adjacentPairs` of size `n - 1` where each `adjacentPairs[i] = [ui, vi]` indicates that the elements `ui` and `vi` are adjacent in `nums`.

It is guaranteed that every adjacent pair of elements `nums[i]` and `nums[i+1]` will exist in `adjacentPairs`, either as `[nums[i], nums[i+1]]` or `[nums[i+1], nums[i]]`. The pairs can appear in any order.

Return the original array `nums`. If there are multiple solutions, return any of them.

Example 1:

    Input: adjacentPairs = [[2,1],[3,4],[3,2]]
    Output: [1,2,3,4]
    Explanation: This array has all its adjacent pairs in adjacentPairs.
    Notice that adjacentPairs[i] may not be in left-to-right order.

Example 2:

    Input: adjacentPairs = [[4,-2],[1,4],[-3,1]]
    Output: [-2,4,1,-3]
    Explanation: There can be negative numbers.
    Another solution is [-3,1,4,-2], which would also be accepted.

Example 3:

    Input: adjacentPairs = [[100000,-100000]]
    Output: [100000,-100000]

Constraints:

- `nums.length == n`
- `adjacentPairs.length == n - 1`
- `adjacentPairs[i].length == 2`
- `2 <= n <= 105`
- `-105 <= nums[i], ui, vi <= 105`
- There exists some `nums` that has `adjacentPairs` as its pairs.