Vertical Order Traversal of Binary Tree

Level-order visualizer: collect nodes by column, then sort by row/value

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Step0/23
Columns0
Result[]
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Python Code

6    queue = deque([(root, 0, 0)])  # node, row, col
7    while queue:
●        node, row, col = queue.popleft()
9        cols[col].append((row, node.data))
10        if node.left:
11            queue.append((node.left, row + 1, col - 1))
12        if node.right:
13            queue.append((node.right, row + 1, col + 1))
14    ans = []
Current Line (8): Pop Queue Head

Tree Structure

123456
Operation:Pop node 1 (row=0, col=0) from queue

Traversal Progress

Current Node

-

Phase

Pop Queue

Result Columns

Traversal result appears here...
Step 1: Pop node 1 (row=0, col=0) from queue

Processing Stack

Stack is empty. Click Next to begin!

Step Explanation

Ready to Start

Click "Next Step" to begin Vertical Order traversal. The flow is level-order (BFS).

  • > Each node is captured with (row, col), then grouped and sorted by col, row, value.
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