What is the algorithm to remove an item from a BST?

What is the algorithm to remove an item from a BST?

Algorithm to delete a node in a Binary Search Tree Input the nodes of the tree. Consider the first element as the root element and insert all the elements. Input the data of the node to be deleted. If the node is a leaf node, delete the node directly.

Which case is the most complicated case to delete a node from BST?

Deleting a node from a BST — Part 2 (the hard case) Deleting a node that has two subtrees is very complicated…. Here is the summary of the procedure: First, we find the deletion node p (= the node that we want to delete)

What is an external node?

An external node is one without child branches, while an internal node has at least one child branch. The sum of the levels of each of the internal nodes in a tree is called the internal path length of that tree. The sum of the levels of each of the external nodes in a tree is called the external path length.

How do you prune a binary tree?

Binary Tree Pruning in C++

1. Define a recursive method solve(), this will take the node.
2. If node is null, then return null.
3. left of node := solve(left of node)
4. right of node := solve(right of node)
5. if left of node is null and right of node is also null and node value is 0, then return null.
6. return node.

How to delete a node from a BST tree?

We have discussed BST search and insert operations. In this post, the delete operation is discussed. When we delete a node, three possibilities arise. 1) Node to be deleted is the leaf: Simply remove from the tree.

Why is deleting a node from a binary search tree so complicated?

Fact: Deleting a node from a Binary Search Tree is very complicated because: The resulting tree after the deletion must also be a Binary Search Tree. The best known algorithm used to delete a node from a Binary Search Tree is called: The Hibbard deletion algorithm Algolist.net: click here.

How to remove 12 from a BST in Python?

Remove 12 from a BST. Find minimum element in the right subtree of the node to be removed. In current example it is 19. Replace 12 with 19. Notice, that only values are replaced, not nodes. Now we have two nodes with the same value. Remove 19 from the left subtree. First, check first if root exists.

How to remove a node from a tree with no children?

Node to be removed has no children. This case is quite simple. Algorithm sets corresponding link of the parent to NULL and disposes the node. Example. Remove -4 from a BST. Node to be removed has one child. It this case, node is cut from the tree and algorithm links single child (with it’s subtree) directly to the parent of the removed node.