Practice Pathfinding and A* with the exercise "11-puzzle"

Learning Opportunities

This puzzle can be solved using the following concepts. Practice using these concepts and improve your skills.

Statement

The Goal

This is a 3 by 4 sliding puzzle with one tile missing. The objective is to place the tiles in order by making sliding moves that use the empty space.

Rules

You are given the initial state of the board and you must output a list of moves to rearrange the tiles.

Each tile is numbered from 1 to 11 (0 is the empty space). The final state is the following:

0  1  2  3
4  5  6  7
8  9 10 11

In order to make a move, you need to print the coordinate of the tile you wish to move and it will take the place of the empty space. The coordinate of a tile is the couple (row, column), with (0, 0) the top-left element.

Victory Conditions

The puzzle is rearranged.

Lose Conditions

Invalid move or the solution exceeds 50 moves.

Game Input

Input

3 lines: 4 space separated integers that represent the initial state of the puzzle.

Output

For each move: two space separated integers that are the ROW and the COLUMN of the tile to move.

Constraints

Response time first turn ≤ 1000ms

Solve it

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