This is an PPT of Data Structure. It include the following topic "Tree Traversal Algorithm in Data Structure".

1. BIRLA INSTITUTE OF
TECHNOLOGY,MESRA
JAIPUR CAMPUS
Presented By:
Apoorva Nagar
MCA/25013/18
TREE TRAVERSAL ALGORITHMS

2. TREE TRAVERSAL
ALGORITHMS

3. BINARY TREES
• A Binary tree is a tree with all nodes having at most two
branches.
• Each node have a degree of at most two.
• Binary tree can be empty or consists of a root node and
two disjoint binary trees termed left subtree and right
subtree

4. BINARY TREE TRAVERSAL
• A traversal of a binary tree is where its nodes are
visited in a particular but in repetitive order.
• A traversal is governed by three action.They are:
Move Left(L)
Move Right(R)
Processed Node(P)
• All these action yield into many different combination
out of which three most significant combination result
into three traversal ways.They are:
Inorder Traversal—LPR
Postorder Traversal—LRP
Preorder Traversal—PLR

5. INORDER TRAVERSAL
ALGORITHM:
Recursive procedure to perform Inorder traversal of a
binary tree.
Procedure INORDER_TRAVERSAL(NODE)
If NODE NIL then
{
call INORDER_TRAVERSAL(LCHILD(NODE));
print (DATA (NODE));
call INORDER_TRAVERSAL(RCHILD(NODE));
}
end INORDER_TRAVERSAL.

6. • The traversal keeps moving left in the binary tree until
one can move no further, processes the node and
moves to the right to continue its traversal again.
• In the absence of any node to the right, it retracts
backward by a node and continue its traversal.
• Consider a binary tree
Inorder traversal output is: G H F I E A B D C

7. POSTORDER TRAVERSAL
ALGORITHM:
Recursive procedure to perform postorder traversal of a
binary tree
Procedure POSTORDER_TRAVERSAL(NODE)
If NODE NIL then
{
call POSTORDER_TRAVERSAL(LCHILD(NODE));
call POSTORDER_TRAVERSAL(RCHILD(NODE));
print (DATA(NODE));
}
end POSTORDER_TRAVERSAL.

8. • The traversal proceeds by keeping to the left until it is no
further possible,turns right to continue its traversal.
• If there is no right node, processes the node and
retraces its direction by one node to continue its
traversal.
• Consider a binary tree
Postorder Traversal output is: G F E I H D C B A

9. PREORDER TRAVERSAL
ALGORITHM:
Recursive procedure to perform preorder traversal of a
binary tree
Procedure PREORDER_TRAVERSAL(NODE)
If NODE NIL then
{
print (DATA (NODE));
call PREORDER_TRAVERSAL(LCHILD(NODE));
call PREORDER_TRAVERSAL(RCHILD(NODE));
}
end PREORDER_TRAVERSAL.

10. • The traversal process every node as it moves to left until
it can move no further.Now it turns right to begin again.
• If there is no node in the right, retracts until it can move
right to continue its traversal.
• Consider a binary tree
Preorder Traversal output is: A H G I F E B C D

11. USES OF TREE TRAVERSAL
In case of binary search trees (BST), Inorder traversal
gives nodes in non-decreasing order.
Preorder and Inorder traversals are used to create a copy
of the tree.
Postorder traversal is used to delete the tree.

12. REFERENCES
https://www.geeksforgeeks.org/tree-traversals-inorder-
preorder-and-postorder/
https://www.tutorialspoint.com/data_structures_algorithms
/tree_traversal.htm

13. THANK YOU!!!