<p>You are given the <code>root</code> of a binary tree with <strong>unique values</strong>.</p>

<p>In one operation, you can choose any two nodes <strong>at the same level</strong> and swap their values.</p>

<p>Return <em>the minimum number of operations needed to make the values at each level sorted in a <strong>strictly increasing order</strong></em>.</p>

<p>The <strong>level</strong> of a node is the number of edges along the path between it and the root node<em>.</em></p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img src="https://assets.leetcode.com/uploads/2022/09/18/image-20220918174006-2.png" style="width: 500px; height: 324px;" />
<pre>
<strong>Input:</strong> root = [1,4,3,7,6,8,5,null,null,null,null,9,null,10]
<strong>Output:</strong> 3
<strong>Explanation:</strong>
- Swap 4 and 3. The 2<sup>nd</sup> level becomes [3,4].
- Swap 7 and 5. The 3<sup>rd</sup> level becomes [5,6,8,7].
- Swap 8 and 7. The 3<sup>rd</sup> level becomes [5,6,7,8].
We used 3 operations so return 3.
It can be proven that 3 is the minimum number of operations needed.
</pre>

<p><strong class="example">Example 2:</strong></p>
<img src="https://assets.leetcode.com/uploads/2022/09/18/image-20220918174026-3.png" style="width: 400px; height: 303px;" />
<pre>
<strong>Input:</strong> root = [1,3,2,7,6,5,4]
<strong>Output:</strong> 3
<strong>Explanation:</strong>
- Swap 3 and 2. The 2<sup>nd</sup> level becomes [2,3].
- Swap 7 and 4. The 3<sup>rd</sup> level becomes [4,6,5,7].
- Swap 6 and 5. The 3<sup>rd</sup> level becomes [4,5,6,7].
We used 3 operations so return 3.
It can be proven that 3 is the minimum number of operations needed.
</pre>

<p><strong class="example">Example 3:</strong></p>
<img src="https://assets.leetcode.com/uploads/2022/09/18/image-20220918174052-4.png" style="width: 400px; height: 274px;" />
<pre>
<strong>Input:</strong> root = [1,2,3,4,5,6]
<strong>Output:</strong> 0
<strong>Explanation:</strong> Each level is already sorted in increasing order so return 0.
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li>The number of nodes in the tree is in the range <code>[1, 10<sup>5</sup>]</code>.</li>
	<li><code>1 &lt;= Node.val &lt;= 10<sup>5</sup></code></li>
	<li>All the values of the tree are <strong>unique</strong>.</li>
</ul>

class Solution:
    def minimumOperations(self, root: Optional[TreeNode]) -> int:
        par = {}
        rank = {}
        
        def ins(n1):
            if n1 in par:
                return
            par[n1] = n1
            rank[n1] = 1
        
        def find(n1):
            while n1 != par[n1]:
                par[n1] = par[par[n1]]
                n1 = par[n1]
            return n1
        
        def union(n1, n2):
            p1, p2 = find(n1), find(n2)
            if p1 == p2:
                return 0
            if rank[p1] < rank[p2]:
                p1, p2 = p2, p1
            par[p2] = p1
            rank[p1] += rank[p2]
            return 1
        
        def helper(nums):
            t = sorted(nums)
            
            for i, j in zip(nums, t):
                ins(i)
                ins(j)
                union(i, j)
            
            return sum(rank[i] - 1 for i in nums if i == find(i))
            
        
        q = deque( [root] )
        res = 0
        
        while q:
            level = []
            
            for _ in range(len(q)):
                cur = q.popleft()
                level.append(cur.val)
                
                if cur.left: q.append(cur.left)
                if cur.right: q.append(cur.right)
                    
            res += helper(level)
        
        return res
559