Dsa
Trees
Warm-up
Count Leaf Nodes
Given a binary tree, count the number of leaf nodes in it. A leaf node is a node that has no children. You should read the tree in a specific format: first read an integer N, the number of nodes, followed by N lines where each line contains a node value and its left and right child indices (0 if there's no child). Print the count of leaf nodes.
Example Input:
5
1 2 3
2 0 0
3 0 0
4 0 0
5 0 0
Example Output:
3
Key concepts
treesrecursioncounting
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