Inorder traversal is a method used to visit all the nodes of a binary tree systematically. In this traversal technique, nodes are visited in a specific order: left subtree, current node, right subtree. Here's how the inorder traversal works:
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Visit the Left Subtree: Start traversing from the root of the binary tree. Recursively traverse the left subtree until you reach a leaf node (a node with no left child).
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Visit the Current Node: Once you reach a leaf node, visit the current node. After visiting the left subtree and the current node, you have completed the left subtree traversal.
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Visit the Right Subtree: After visiting the current node, recursively traverse the right subtree using the same process: first the left subtree, then the current node, and finally the right subtree.
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Repeat the Process: Repeat steps 1-3 for each subtree until you have visited all nodes in the binary tree.
Here's a simple pseudocode representation of the inorder traversal algorithm:
inorderTraversal(node):
if node is not null:
inorderTraversal(node.left)
visit(node)
inorderTraversal(node.right)
This pseudocode recursively traverses the left subtree, visits the current node, and then recursively traverses the right subtree. The visit(node) function represents what happens when a node is visited; it could be printing the node's value, storing it in a list, or performing some other operation.
In terms of its applications, inorder traversal is commonly used in binary search trees (BSTs) to retrieve all elements in sorted order. Because of the order in which nodes are visited (left, current, right), inorder traversal produces a sorted sequence of elements when applied to a binary search tree. This property makes inorder traversal useful for tasks that require accessing elements in a sorted order, such as searching, iterating, or printing elements of a BST.
