Why is the brute-force approach less ideal here?

Question

Why is the brute-force approach less ideal here?

Option A — Correct answer

Updating every later prefix value costs O(n).

Option B

It always uses no memory

Option C

It avoids all state changes

Option D

It only works for binary search

Explanation

Updating every later prefix value costs O(n).

Fenwick Tree - Binary Indexed Prefix Sum Pattern Practice Quiz