All challenges

Build a bounded-size tree of small vertex sets that covers tree and outer-ring edges.

Place many grid points while avoiding the four corners of every axis-aligned rectangle.

Construct a small binary grid with exactly the requested number of monotone paths.

Construct a compact weighted DAG whose paths represent exactly one integer interval.

Construct a permutation whose increasing-subsequence count matches the target value.

Move stacked colored balls among pillars until each color occupies one pillar.