Dsa
Trees
Medium
Count Nodes at Even Levels
You are given a binary tree, and you need to count the number of nodes that are located at even levels (0-indexed).
Input format:
The input starts with an integer n, the number of nodes (1 <= n <= 1000). Then, n lines follow, each containing the node value and the left and right children values (or -1 if no child).
Output format:
Print a single integer indicating the count of nodes at even levels.
Example:
Input:
5
1 2 3
2 -1 -1
3 4 5
4 -1 -1
5 -1 -1
Output:
3
Key concepts
treeslevel order traversal
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