powersort's pursuit · a merge game

Merge the runs.
Pay as little as you can.

The input is already cut into sorted runs. Merge two neighbours by dragging one onto the other; the result is a new block, and every merge costs the length of the block it creates. Keep merging until a single block is left — the total you paid is your score. Lower is better. nH is a floor no merge tree can beat, and n(H+2) is what a good merge policy guarantees; where do you land?

level 1 first steps

merge cost so far 0

drag a framed block onto a highlighted neighbour · or click a block, then click a neighbour · ←→ select shift+←→ merge that way u undo y redo r start over

input

level run lengths

random input n runs

cost

leaderboard

player

import / export a merge tree

load file…

The export is valid Python: runs is the input, merges lists the merges in play order as positions — k means “merge blocks k and k+1, counting all current blocks from the left”, exactly what a policy(runs) in the workshop page returns. Import also accepts spans (i, j), a bare list of positions for the current input, JSON, or a tree literal like ((5 3) (3 14)).

legend

block you can still merge input run merge picked up / possible partner already merged away

Merge the runs.Pay as little as you can.

Merge the runs.
Pay as little as you can.