<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>

# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right
class Solution:

    def minimumOperations(self, root: Optional[TreeNode]) -> int:

        def perm(lis):
           # print(lis)
            visited = set()
            sorted_lis = sorted(lis)
            idx_map = {n:i for i, n in enumerate(sorted_lis)}
            result = 0
            for i in range(len(lis)):
                if i in visited or idx_map[lis[i]] == i:
                    continue
                cycle = 0
                cur = i
                while cur not in visited:
                    visited.add(cur)
                    cur = idx_map[lis[cur]]
                    cycle += 1
                if cycle > 0:
                    result+= (cycle - 1)
            return result

        if not root:
            return 0
        q = deque()
        result = 0
        q.append(root)
        while q:
            result += perm([x.val for x in q])
            for _ in range(len(q)):
                x = q.popleft()
                if x.left:
                    q.append(x.left)
                if x.right:
                    q.append(x.right)
                    
        return result
47500