Fenwick Tree’s efficiency, combined with its relatively simple implementation, makes it useful in competitive programming and applications that involve dynamic sum queries and updates.
This problem, also referred to as the “sliding window maximum” problem, can be efficiently solved using heaps. We’ve already discussed an O(n) solution.
Subsequences derived from strings by deleting some or no characters without changing order, are crucial in fields like bioinformatics, data mining, and cryptography.