Description:
A Maze is given as N*N binary matrix of blocks where source block is the upper left most block i.e., maze[0][0] and destination block is lower rightmost block i.e., maze[N-1][N-1]. A rat starts from source and has to reach the destination. The rat can move only in two directions: forward and down.
In the maze matrix, 0 means the block is a dead end and 1 means the block can be used in the path from source to destination. Note that this is a simple version of the typical Maze problem. For example, a more complex version can be that the rat can move in 4 directions and a more complex version can be with a limited number of moves.
Following is an example maze.
Gray blocks are dead ends (value = 0).
Following is binary matrix representation of the above maze.
{1, 0, 0, 0} {1, 1, 0, 1} {0, 1, 0, 0} {1, 1, 1, 1} Following is a maze with highlighted solution path.
Following is the solution matrix (output of program) for the above input matrx.
{1, 0, 0, 0} {1, 1, 0, 0} {0, 1, 0, 0} {0, 1, 1, 1} All enteries in solution path are marked as 1.
Solution:
class Main { public static void main(String[] args) { Main rat = new Main(); int maze[][] = { { 1, 0, 0, 0 }, { 1, 1, 0, 1 }, { 0, 1, 0, 0 }, { 1, 1, 1, 1 } }; int [][] sol = new int[4][4]; if(rat.CheckSol(maze,0,0,sol)){ rat.printSolution(sol); } } void printSolution(int sol[][]) { for (int i = 0; i < sol.length; i++) { for (int j = 0; j < sol[0].length; j++) System.out.print(" " + sol[i][j] + " "); System.out.println(); } } boolean CheckSol(int[][]maze, int i, int j, int[][] sol){ //goal if(i==maze.length-1 && j ==maze[0].length-1){ sol[i][j]=1; return true; } if(isSafe(maze,i,j)){ sol[i][j] = 1; if(CheckSol(maze,i+1,j,sol)){ return true; } if(CheckSol(maze,i,j+1,sol)){ return true; } sol[i][j]=0; return false; } return false; } boolean isSafe(int[][] maze, int i , int j ){ if((i>=0 &&i<maze.length )&& (j>=0&&j<maze[0].length)&&maze[i][j]==1){ return true; } return false; } }