Range Min - Update Challenge

Point updates for range min are more expensive than for range sum.

When you update $arr[i]$, you must recompute $blockMin[\lfloor i/B \rfloor]$ by scanning all elements in that block. The operation takes $O(B) = O(\sqrt{n})$ time.

For range sum, updates were $O(1)$. For range min, updates are $O(\sqrt{n})$. Both queries remain $O(\sqrt{n})$. If updates are rare, this is fine. If updates are frequent, consider segment trees or sparse tables for better update complexity.