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Retranslate the complete English edition from Simplified Chinese (#2010)

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* Retranslate the complete English edition from Simplified Chinese

* Polish three English explanations after reader-focused review
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Yudong Jin
2026-10-31 03:35:51 +08:00
committed by GitHub
parent ef46e2ed95
commit 14c314c08c
1502 changed files with 29459 additions and 23517 deletions
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50
en/codes/python/chapter_tree/array_binary_tree.py
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@@ -12,39 +12,39 @@ from modules import TreeNode, list_to_tree, print_tree
class ArrayBinaryTree:
"""Binary tree class represented by array"""
"""Binary tree class using an array representation"""
def __init__(self, arr: list[int | None]):
"""Constructor"""
self._tree = list(arr)
def size(self):
"""List capacity"""
"""Length of the backing list"""
return len(self._tree)
def val(self, i: int) -> int | None:
"""Get value of node at index i"""
# If index is out of bounds, return None, representing empty position
"""Get the value of the node at index i"""
# If the index is out of bounds, return None to represent an empty position
if i < 0 or i >= self.size():
return None
return self._tree[i]
def left(self, i: int) -> int | None:
"""Get index of left child node of node at index i"""
"""Get the left child index of the node at index i"""
return 2 * i + 1
def right(self, i: int) -> int | None:
"""Get index of right child node of node at index i"""
"""Get the right child index of the node at index i"""
return 2 * i + 2
def parent(self, i: int) -> int | None:
"""Get index of parent node of node at index i"""
"""Get the parent index of the node at index i"""
return (i - 1) // 2
def level_order(self) -> list[int]:
"""Level-order traversal"""
self.res = []
# Traverse array directly
# Traverse the array directly
for i in range(self.size()):
if self.val(i) is not None:
self.res.append(self.val(i))
@@ -85,35 +85,35 @@ class ArrayBinaryTree:
return self.res
"""Driver Code"""
"""Driver code"""
if __name__ == "__main__":
# Initialize binary tree
# Here we use a function to generate a binary tree directly from an array
# Initialize the binary tree
# Use a helper function that builds a binary tree directly from an array
arr = [1, 2, 3, 4, None, 6, 7, 8, 9, None, None, 12, None, None, 15]
root = list_to_tree(arr)
print("\nInitialize binary tree\n")
print("Array representation of binary tree:")
print("\nInitialize the binary tree\n")
print("Array representation of the binary tree:")
print(arr)
print("Linked list representation of binary tree:")
print("Linked representation of the binary tree:")
print_tree(root)
# Binary tree class represented by array
# Binary tree class using an array representation
abt = ArrayBinaryTree(arr)
# Access nodes
# Access a node
i = 1
l, r, p = abt.left(i), abt.right(i), abt.parent(i)
print(f"\nCurrent node's index is {i}, value is {abt.val(i)}")
print(f"Its left child node's index is {l}, value is {abt.val(l)}")
print(f"Its right child node's index is {r}, value is {abt.val(r)}")
print(f"Its parent node's index is {p}, value is {abt.val(p)}")
print(f"\nCurrent node index: {i}, value: {abt.val(i)}")
print(f"Left child index: {l}, value: {abt.val(l)}")
print(f"Right child index: {r}, value: {abt.val(r)}")
print(f"Parent index: {p}, value: {abt.val(p)}")
# Traverse tree
# Traverse the tree
res = abt.level_order()
print("\nLevel-order traversal is:", res)
print("\nLevel-order traversal:", res)
res = abt.pre_order()
print("Preorder traversal is:", res)
print("Preorder traversal:", res)
res = abt.in_order()
print("Inorder traversal is:", res)
print("Inorder traversal:", res)
res = abt.post_order()
print("Postorder traversal is:", res)
print("Postorder traversal:", res)