Data Structures and Algorithms · Advanced structures

Fenwick trees

A compact array-based structure that answers prefix-sum queries in logarithmic time.

Also known as: binary indexed tree, BIT, prefix sum tree.

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• Arrays: A fixed-layout, contiguous block of memory where any index is reached in constant time.

Related topics

• Segment trees: A binary tree over an array that answers range queries, like sum or minimum, in logarithmic time.