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Binary TreesEasyLeetCode #145

3. Postorder Traversal (Left → Right → Root) ⭐

Traverses both left and right subtrees completely before processing the parent node. Essential for bottom-up calculations.

Time O(n) Space O(h)
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Asked in interviews at

AmazonGoogle

Reference implementation (Python)

def postorder(root):
    res = []
    def dfs(node):
        if not node:
            return
        dfs(node.left)
        dfs(node.right)
        res.append(node.val)
    dfs(root)
    return res

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Drop a live, looping 3. Postorder Traversal (Left → Right → Root) ⭐ canvas into a blog post or course page.

<iframe src="/embed/tree-postorder" width="100%" height="380" style="border:1px solid #e6e8ec;border-radius:14px" loading="lazy" title="3D algorithm visualization by CodeWithMunnaX"></iframe>

Frequently asked

What is the time and space complexity of 3. Postorder Traversal (Left → Right → Root) ⭐?

3. Postorder Traversal (Left → Right → Root) ⭐ runs in O(n) time and O(h) auxiliary space.

Is the 3. Postorder Traversal (Left → Right → Root) ⭐ visualizer free?

The core 3D visualizer, Web Audio chimes and step intuition are free. A one-time ₹49 Pro Pass unlocks advanced algorithms, large custom arrays, Battle Arena and reel export.

Which companies ask 3. Postorder Traversal (Left → Right → Root) ⭐ in interviews?

3. Postorder Traversal (Left → Right → Root) ⭐ shows up in interviews at Amazon, Google.

How does the 3D visualization of 3. Postorder Traversal (Left → Right → Root) ⭐ work?

Each array value becomes a 3D pillar whose height maps to its value. Comparisons glow amber, swaps flash red, and settled elements lock green while a floating pointer badge tracks the active index — synchronized line-by-line with the Python code.

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