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core15 min

Binary Tree Level Order Traversal

Binary Tree Level Order Traversal

Return the tree's values grouped level by level, top to bottom (BFS), as an array of arrays. Process one full queue "generation" at a time rather than mixing levels together.

levelOrder(tree([3, 9, 20, null, null, 15, 7])); // [[3], [9, 20], [15, 7]]

Run your code to see results.

Stuck? This challenge exercises:

javascript.data-structures