Tree Traversal
- 1. Dept. of Computer science of Engineering Batch: Spring 2022- 221-DA Date: 10/05/2022 Course teacher: Md. Suntanul Islam Ovi Subject: Discrete Math Topic: Tree Traversal
- 2. Md. Sabbir Hossain ID: 221902126 Md. Israil Fakir ID: 221902125 Dina Azad ID: 221902123 Md. Emam Hossain ID: 221902124
- 3. Tree Traversal What is Tree Traversal ? Tree traversal means visiting each node of the tree However, in tree data structures, there are multiple ways to traverse it.
- 4. Tree Traversal Types of Tree Traversal There are three types of tree traversal. In-order Traversal Tree Traversal Pre-order Traversal Post-order traversal
- 5. Pre-order Traversal Preorder traversal 1. Visit root node 2. Visit all the nodes in the left subtree 3. Visit all the nodes in the right subtree In this traversal method, the root node is visited first, then the left subtree and finally the right subtree
- 6. Pre-order Traversal Example: Solution: 1 2 4 5 3
- 7. Pre-order Traversal Algorithm: Pre-order traversal procedure preorder (T: Ordered rooted tree ) r:=root of T List r For each child c of r from left to right begin T(c):= subtree with c as its root Preorder ( T(c)) end T r b c d e g f k h i j
- 8. In-order Traversal In this traversal method, the left subtree is visited first, then the root and later the right sub-tree. We should always remember that every node may represent a subtree itself. In-order traversal 1. Visit all the nodes in the left subtree 2. Visit root node 3. Visit all the nodes in the right subtree
- 9. In-order Traversal Example: Solution: 4 2 5 1 3
- 10. In-order Traversal T r b c d e g f k h i j Algorithm: In-order traversal Procedure In-order (T: ordered rooted tree) r := root of T If r is a leaf then list r else begin l := first child of from left to right T (l) := subtree with l as its root In-order( T(l)) list r for each child c of r except for l from left to right T ( c):= subtree with c as its root In-order(T(c)) end
- 11. Post-order Traversal In this traversal method, the root node is visited last, hence the name. First we traverse the left subtree, then the right subtree and finally the root node. In-order traversal 1. Visit all the nodes in the left subtree 2. Visit all the nodes in the right subtree 3. Visit root node
- 12. Post-order Traversal Example: Solution: 4 5 2 3 1
- 13. Pre-order Traversal T r b c d e g f k h i j Algorithm: Post-order traversal Procedure post-order(T : ordered rooted tree) r :=root of T For each child c of r from left to right Begin T(c) := subtree with c as its root Post-order (T(c)) end List r
- 14. Thank you