SQRT Decomposition
Problems on SQRT decomposition, including splitting an array into blocks of size \sqrt{n}, range updates and queries by blocks, Mo's algorithm for offline queries, and splitting work between heavy and light elements.
Related problem sets are under Queries, Segment tree and Range queries.
Problems
Circles#5959
Very hard
Cossack Vus and the Count#11076
Very hard
No legend#11514
Very hard
Boring tree queries#11544
Very hard
Lamps#11692
Medium
Good Host#12266
Very hard
Oh no, sorting#12371
Very hard