Question

Consider a node R of a complete binary tree whose value is stored in position i of an array representation for the tree. If R has a left sibling, where will the left sibling's position be in the array?

a. i+1
b. 2∗i+2
c. i−1
d. None of the above

Answer 1

In an array representation of a complete binary tree, the left sibling of node R at position i will be located at position i-1.

Step-by-step explanation:

If we consider a node R that is stored at position i in an array representation of a complete binary tree, the position of R's left sibling can be determined by understanding the binary tree properties and how these trees are typically implemented as arrays.

In a complete binary tree, the children of the node at position i are found at 2*i+1 (left child) and 2*i+2 (right child). Therefore, if a node has a left sibling, it means that the node is a right child. Since the right child is at position i, the left child must be immediately before it, at position i-1. Hence, the correct answer would be c. i-1.