Question Bank
Binary Tree Basics Quiz
Difficulty: Easy
Short prompts on node anatomy, depth vs height, and leaf counting. Foundation drills before tackling traversal, BSTs, or balanced tree problems.
Binary Tree Basics Quiz
Short prompts on node anatomy, depth vs height, and leaf counting. Foundation drills before tackling traversal, BSTs, or balanced tree problems.
Question Bank
Easy
JavaScript
3 questions
binary-tree
data-structures
quiz
fundamentals
1,121 views
9
For the tree built below, identify (a) the root, (b) every leaf, (c) the height of the tree, and (d) the depth of node 5.
Examples
Example 1:
Input: tree 1 with left subtree (2 -> (4, 5)) and right subtree (3 -> (null, 6))
Output: root = 1; leaves = {4, 5, 6}; height (edges) = 2; depth(5) = 2
Explanation: Root is the topmost node. Leaves are nodes with no children. Counting in edges, the root sits at height 2 and leaves at 0. Node 5 is two edges from the root.Implement countLeaves(root) returning the number of leaf nodes in a binary tree. Recursion is fine; aim for O(n) time, O(h) space.
Examples
Example 1:
Input: tree 1 -> (2 -> (4, 5), 3)
Output: 3
Explanation: Nodes 4, 5, and 3 are leaves (both children null), nodes 1 and 2 are internal. Recursion returns 0 for null, 1 for leaves, and the sum of subtree counts otherwise.Example 2:
Input: tree = single node 7
Output: 1
Explanation: A solitary root is itself a leaf, so the count is 1.Explain the difference between depth and height in a binary tree, and state both for the root and for every leaf using one convention.