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1c0f350ad6
* Add the intial translation of code of all the languages * test * revert * Remove * Add Python and Java code for EN version
66 lines
1.6 KiB
Python
66 lines
1.6 KiB
Python
"""
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File: binary_tree_dfs.py
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Created Time: 2022-12-20
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Author: a16su (lpluls001@gmail.com)
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"""
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import sys
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from pathlib import Path
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sys.path.append(str(Path(__file__).parent.parent))
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from modules import TreeNode, list_to_tree, print_tree
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def pre_order(root: TreeNode | None):
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"""Pre-order traversal"""
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if root is None:
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return
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# Visit priority: root node -> left subtree -> right subtree
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res.append(root.val)
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pre_order(root=root.left)
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pre_order(root=root.right)
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def in_order(root: TreeNode | None):
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"""In-order traversal"""
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if root is None:
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return
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# Visit priority: left subtree -> root node -> right subtree
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in_order(root=root.left)
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res.append(root.val)
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in_order(root=root.right)
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def post_order(root: TreeNode | None):
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"""Post-order traversal"""
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if root is None:
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return
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# Visit priority: left subtree -> right subtree -> root node
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post_order(root=root.left)
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post_order(root=root.right)
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res.append(root.val)
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"""Driver Code"""
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if __name__ == "__main__":
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# Initialize binary tree
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# Use a specific function to convert an array into a binary tree
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root = list_to_tree(arr=[1, 2, 3, 4, 5, 6, 7])
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print("\nInitialize binary tree\n")
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print_tree(root)
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# Pre-order traversal
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res = []
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pre_order(root)
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print("\nPrint sequence of nodes from pre-order traversal = ", res)
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# In-order traversal
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res.clear()
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in_order(root)
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print("\nPrint sequence of nodes from in-order traversal = ", res)
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# Post-order traversal
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res.clear()
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post_order(root)
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print("\nPrint sequence of nodes from post-order traversal = ", res)
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