## What is left right rotation in AVL tree?

AVL tree may become unbalanced, if a node is inserted in the left subtree of the left subtree. The tree then needs a right rotation. As depicted, the unbalanced node becomes the right child of its left child by performing a right rotation.

**How do you identify a tree that is left heavy and right heavy in AVL tree?**

Using the definition for balance factor given above we say that a subtree is left-heavy if the balance factor is greater than zero. If the balance factor is less than zero then the subtree is right heavy. If the balance factor is zero then the tree is perfectly in balance.

**What are double and single threaded trees?**

What are double and single threaded trees? Explanation: They are properties of double and single threaded binary trees respectively. Explanation: Property of inorder threaded binary tree is left node with inorder predecessor and right node with inorder successor information are stored.

### What is single and double rotation in AVL tree?

The key to an AVL tree is keeping it balanced when an insert or delete operation is performed. If we start with an AVL tree, then what is needed is either a single rotation or a double rotation (which is two single rotations) on the unbalanced node and that will always restore the balance property in O(1) time.

**What is AVL tree in DSA?**

AVL tree is a self-balancing Binary Search Tree (BST) where the difference between heights of left and right subtrees cannot be more than one for all nodes. An Example Tree that is an AVL Tree. The above tree is AVL because differences between heights of left and right subtrees for every node is less than or equal to 1 …

**How do you tell if a tree is an AVL tree?**

What is an AVL Tree?

- Each tree has a root node (at the top)
- The root node has zero, one, or two child nodes.
- Each child node has zero, one, or two child nodes.
- Each node has up to two children.
- For each node, its left descendants are less than the current node, which is less than the right descendants.

## What is AVL tree explain with an example?

**Why do you like red black trees over AVL trees?**

When it would be optimal to prefer Red-black trees over AVL trees? Explanation: Though both trees are balanced, when there are more insertions and deletions to make the tree balanced, AVL trees should have more rotations, it would be better to use red-black.

**How many child nodes does a node of AVL tree have?**

2-3 trees require that all paths from the root to leaves are exactly the same length, but allow internal nodes to have two or three children. AVL trees require the heights of the subtrees of any node to differ by no more than one level, which ensures that the height is O(log N).