Q. What do you understand by the tree traversal? Write down the procedure for traversing a binary tree in preorder and execute it on the following tree.
The algorithm walks through tree data structure and performs some calculation at each node in the tree. This procedure of walking through the tree is called a tree traversal.
There are basically two different methods in which to visit systematically all the nodes of a tree-the depth-first traversal and the breadth-first traversal. Certain depth- first traversal methods happen frequently enough that they are given names of their own: preorder traversal, inorder traversal and postorder traversal.
The algorithm for traversing a tree in preorder is written as follows:-
i. Process the root R.
ii. Traverse left sub tree of R in preorder. iii. Traverse right sub tree of R in preorder. The preorder for the given tree is as follows:-
A L1 R1
A B L1l L1R R1
A B D L1R R1
A B D E R1
A B D E C R1L R1R
A B D E C F R1R
A B D E C F G