Right Rotate
In left-rotation, the arrangement of the nodes on the left is transformed into the arrangements on the right node.
1. Let the initial tree be:
2. If x has a right subtree, assign y as the parent of the right subtree of x.
3. If the parent of y is NULL, make x as the root of the tree.
4. Else if y is the right child of its parent p, make x as the right child of p.
5. Else assign x as the left child of p.
6. Make x as the parent of y.
