Get started

1. Choose a Seed to generate an input in Input.
2. Run your solution locally and paste its output into Output.
3. Press ▶ to play the animation. Use the slider to change the display position, and Speed to adjust the playback speed.

Load and save

• Download: save #cases inputs, starting from Seed.
• Select directory: choose a folder of output files and switch between them. Names such as 1234.txt or abcd_1234.txt automatically select seed 1234; other names use seed 0.
• Export: save the current image as PNG, or the animation as GIF or Video at the current Speed.

Bricks and holes

• The reddish-brown rectangles are bricks. Variations in color and surface texture are decorative and do not indicate brick types or states.
• Circles mark hole positions. Teal indicates a hole covered by a brick, and red indicates an uncovered hole.
• The short line at the bottom center of each brick is its connector. It is dark gray when supported and red when the cell directly below the center is empty. The thick line below the wall is the floor.
• The bottom-left cell is (0, 0), with x increasing to the right and y increasing upward. Hover over a cell to see its coordinates, whether it contains a hole, and information about the brick covering it.

Switching between solutions

• Use t or the slider to switch between complete arrangements. t = 0 is the first solution. Playback displays the solutions in output order.
• Score is the score of the displayed solution, Cost is its total cost, Bricks is the number of bricks, and Covered is the number of covered holes.
• For an invalid arrangement, the score is displayed as 0 and the reason appears in red. If the output format is invalid, the hole positions and the error are displayed.
• Only the last solution is used for scoring. However, an invalid format or an out-of-range value in any earlier solution makes the entire output invalid.