Think of each value in binary. To find values in a range, you can filter by bit positions.
For alphabet (3 bits): - Values with highest bit 0: - Values with highest bit 1: If you're looking for values in , you need some from each group.
The wavelet tree recursively partitions values by their bits. At each level, you split: values with bit 0 go left, values with bit 1 go right. You get us a binary tree of depth where each node handles a range of values.