Extract Leaves of a Binary Tree in a Doubly Linked List : GeeksforGeeks

Problem link: http://www.geeksforgeeks.org/connect-leaves-doubly-linked-list/

Problem Statement:
Given a Binary Tree, extract all leaves of it in a Doubly Linked List (DLL). Note that the DLL need to be created in-place. Assume that the node structure of DLL and Binary Tree is same, only the meaning of left and right pointers are different. In DLL, left means previous pointer and right means next pointer.

Solution Idea:
The first step is to be able to print the leaves. It is simple, you can do a in-order traversal and put a condition (isLeaf) before printing. When you understand this, the rest is making the program work with the boundary conditions. To trim the original tree, we need the reference to the parent pointer in the recursive call.

Solution Gist:

Advertisements

Tagged: , , , , , , , , ,

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: