Bigger Sokoban 40k

Design a bounded Sokoban layout with a solvable 2x2 box puzzle and large minimum distance.

Solution Interface

Submit a zip_project solution. The run command is executed once per case, reads the case from standard input, and writes the answer to standard output. The trusted separated evaluator runs the migrated Frontier-CS Testlib checker against the submitted output and the case's evaluator-only answer or scoring metadata.

Scoring

The leaderboard score is the average checker ratio scaled to 0..100 across official cases. Invalid outputs receive zero for the affected case. The public validation case is intentionally tiny and deterministic; official scoring uses the source-derived Frontier-CS cases packaged as private benchmark data.

Original Statement

Bigger Sokoban 40k Time Limit: 2 seconds Memory Limit: 1024 MB

Problem Sokoban is a famous puzzle game where a player moves around in a grid and pushes boxes to their storage locations.

Bigger Sokoban is a variation of Sokoban where both the boxes and the storage locations are larger than 1×1. In this version, both boxes and storage locations are 2×2 in size.

The rules are the same as in the original Sokoban:

• Each cell in the grid is either empty or a wall.
• Some 2×2 areas of empty squares contain a box, and some 2×2 areas are marked as storage locations.
• The player may move up, down, left, or right into adjacent empty squares, but cannot pass through walls, boxes, or go outside the grid.
• If the player moves into a box, the box is pushed one square in that direction, provided that doing so does not push it into a wall, another box, or outside the grid.
• Boxes cannot be pulled.
• The number of boxes equals the number of storage locations.
• The puzzle is solved when all boxes are placed on the storage locations.

The grid must satisfy the following constraints:

• The grid contains one box and one storage location (each 2×2).
• The player, the box, and the storage location must not overlap.
• 1 ≤ N, M, N + M ≤ 100

Input There is no input for this problem.

Output On the first line, print two integers N and M, the grid size. Then print N lines of length M, describing the grid. Each character must be one of the following:

• '.' : empty square
• '#' : wall
• 'P' : player
• 'B' : box (2×2 block)
• 'S' : storage location (2×2 block)

The grid must contain exactly:

• 1 player (P)
• 4 'B' cells forming a single 2×2 square
• 4 'S' cells forming a single 2×2 square The grid must be solvable.

Example Output (Note: This is just an example of correct format.) 5 6 ....SS ....SS .#BB#. ..BB.P ......

Scoring Your program must output a valid and solvable grid according to the above format. Your solution will be evaluated by a checker program that computes the minimum number of moves required to solve your grid.

Scoring rule:

• 63,000 moves → 100 points
• 0 moves → 0 points
• Linear scaling between them.

Formula: score = min(100, max(0, moves / 630))

Task Write a C++ program that outputs one valid grid satisfying the above conditions to standard output. Your goal is to maximize the minimum number of moves needed to solve the puzzle.