Introduction to array based binary trees

Let us look at a complete binary tree. We can see a pattern if we try to enumerate the nodes of a complete binary tree (assign each node an integer label starting from 0), starting from the root and going top to bottom, left to right.

We can see that for any node with enumeration `n` (so the root is `n = 0`):

• The left child = (2 * n) + 1
• The right child = (2 * n) + 2