Solution Review: Create a Complete Binary Tree

Let’s go through the detailed solution review of the challenge given in the previous lesson.


To create a complete binary tree, we fill the elements in the tree level-by-level, starting from level 0. The steps to create a complete binary tree are as follows:

  • Insert the first element present in the array (index i = 0) as the root node at level 0 of the tree.
  • Calculate left child as 2 * i + 1 and add it in the left subtree of the root.
  • Calculate right child as 2 * i + 2 and add it in the right subtree of the root.
  • Recursively, apply these steps for left and right subtree nodes.

Solution code

Let’s look at the implementation of the levelOrderBinaryTree() function.

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