Build a Tree and Perform BFS Traversal

Problem Given input data that describes a tree structure, you need to: Build a tree from the input (you may design/implement the node structure and building logic); Run BFS (level-order traversal) on the constructed tree; Output the BFS traversal result as required. Input The original prompt did not specify an exact input format (e.g., level-order array, edge list, parent-child pairs, etc.). Output The original prompt did not specify the exact output format (e.g., a flat level-order list, grouping by levels, etc.). Note: The interview recollection is incomplete; the exact I/O specification must be clarified to make this a fully implementable coding question.