forked from UNN/2026-rff_mp
[1] Implement binary search tree (BST) for phonebook
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SavelevMI/docs/data/1-st-exersize/bst.py
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66
SavelevMI/docs/data/1-st-exersize/bst.py
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# Двоичное дерево поиска (не сбалансированное)
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def create_node(name, phone):
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return {'name': name, 'phone': phone, 'left': None, 'right': None}
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def bst_insert(root, name, phone):
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if root is None:
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return create_node(name, phone)
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if name == root['name']:
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root['phone'] = phone
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elif name < root['name']:
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root['left'] = bst_insert(root['left'], name, phone)
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else:
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root['right'] = bst_insert(root['right'], name, phone)
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return root
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def bst_find(root, name):
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if root is None:
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return None
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if name == root['name']:
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return root['phone']
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elif name < root['name']:
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return bst_find(root['left'], name)
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else:
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return bst_find(root['right'], name)
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def _find_min(node):
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while node['left'] is not None:
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node = node['left']
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return node
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def bst_delete(root, name):
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if root is None:
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return None
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if name < root['name']:
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root['left'] = bst_delete(root['left'], name)
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elif name > root['name']:
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root['right'] = bst_delete(root['right'], name)
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else:
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# Нашли узел, который нужно удалить
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if root['left'] is None:
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return root['right']
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if root['right'] is None:
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return root['left']
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# Узел имеет двух потомков: заменяем наименьшим из правого поддерева
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min_node = _find_min(root['right'])
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root['name'] = min_node['name']
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root['phone'] = min_node['phone']
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root['right'] = bst_delete(root['right'], min_node['name'])
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return root
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def bst_list_all(root):
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result = []
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def inorder(node):
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if node is None:
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return
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inorder(node['left'])
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result.append((node['name'], node['phone']))
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inorder(node['right'])
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inorder(root)
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return result
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