Please refer below post before reading about AVL tree handling of duplicates.
This is to augment AVL tree node to store count together with regular fields like key, left and right pointers.
Insertion of keys 12, 10, 20, 9, 11, 10, 12, 12 in an empty Binary Search Tree would create following.
12(3) / \ 10(2) 20(1) / \ 9(1) 11(1)
Count of a key is shown in bracket
Below is implementation of normal AVL Tree with count with every key. This code basically is taken from code for insert and delete in AVL tree. The changes made for handling duplicates are highlighted, rest of the code is same.
The important thing to note is changes are very similar to simple Binary Search Tree changes.
Pre order traversal of the constructed AVL tree is 9(2) 5(2) 7(1) 10(1) 17(1) Pre order traversal after deletion of 9 9(1) 5(2) 7(1) 10(1) 17(1)
Thanks to Rounaq Jhunjhunu Wala for sharing initial code. Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above
- Find All Duplicate Subtrees
- Check if a Binary Tree (not BST) has duplicate values
- Check if a Binary Tree contains duplicate subtrees of size 2 or more
- Count the nodes of a tree whose weighted string does not contain any duplicate characters
- Print BST keys in the given range
- BST to a Tree with sum of all smaller keys
- Insertion in n-ary tree in given order and Level order traversal
- Red-Black Trees | Top-Down Insertion
- m-WAY Search Trees | Set-1 ( Searching )
- Implementing a BST where every node stores the maximum number of nodes in the path till any leaf
- Number of distinct pair of edges such that it partitions both trees into same subsets of nodes
- String Range Queries to find the number of subsets equal to a given String
- Queries for number of distinct elements in a subarray | Set 2
- Maximum XOR with given value in the path from root to given node in the tree