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Thread: Recursion Maze

  1. #1
    Junior Member
    Join Date
    Oct 2010
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    Default Recursion Maze

    Heres what I have:
    import java.io.*;
     
    public class Driver {
    	private File mapFile = new File("map.txt");
    	private char[][]maze;
    	private char pathMarker = 'a';
    	private int row,col,ndx=0;
    	public static void main(String[] args) {
    		Driver d = new Driver();
    	}
    	public Driver(){
    		loadMap(mapFile);
    		row=startRow(maze);
    		col=startColumn(maze);
    		maze[row][col]=' ';
    		findPath(maze,row,col);
    		for (int i = 0; i < maze.length; i++) {
    	        for (int j = 0; j < maze[i].length; j++) {
    	            System.out.print(maze[i][j]);
    	        }
    	        System.out.println();
    	    }
    	}
     
    	private void loadMap(File f){
    		try{
    			String line,line2;
    			int ndx=0,ndx2=0;
    			FileReader fReader,fReader2;
    			BufferedReader reader,reader2;
    			fReader = new FileReader(f);
    			reader = new BufferedReader(fReader);
    			while ((line = reader.readLine()) != null ) {
    				ndx++;
    			}
    			reader.close();
    			fReader2 = new FileReader(f);
    			reader2 = new BufferedReader(fReader2);
    			maze = new char [ndx][];
    			while ((line2 = reader2.readLine()) != null) {
    			    maze[ndx2] = line2.toCharArray();
    			    ndx2++;
    			}
    			reader2.close();
    		}catch(IOException e){
    			System.out.println("INVALID FILE");
    		}
    	}
    	  public int startRow(char [][]arr){
    		  int z=0;
    		  for(int i=0;i!=arr.length;i++){
    			  for(int j=0; j!=arr[i].length;j++){
    				  if(arr[i][j]=='a'){
    					  z=i;
    				  }
    			  }
    		  }return z;
    	  }
    	  public int startColumn(char[][]arr){
    		  int z=0;
    		  for(int i=0;i!=arr.length;i++){
    			  for(int j=0; j!=arr[i].length;j++){
    				  if(arr[i][j]=='a'){
    					  z=j;
    				  }
    			  }
    		  }return z;  
    	  }
    	  public boolean endFound(char[][] arr,int r, int c){
    		  if ((!(r < arr.length)) || r < 0) {
    		        return false;
    		    }
     
    		    if ((!(c < arr[r].length)) || c < 0) {
    		        return false;
    		    }
     
    		    if ((r - 1) > -1) {
    		        if (arr[r - 1][c] == '*') {
    		            return true;
    		        }
    		    }
    		    else if((r+1) <= arr.length){
    		    	if(arr[r+1][c] =='*'){
    		    		return true;
    		    	}
    		    }
    		    else if((c-1)>-1){
    		    	if(arr[r][c-1]=='*'){
    		    		return true;
    		    	}
    		    }
    		    else if((c+1)<=arr[r].length){
    		    	if(arr[r][c+1]=='*'){
    		    		return true;
    		    	}
    		    }
    			return false;
    	  }
    	  public boolean findPath(char[][] arr, int r, int c){
     
    			  if(r<0 || r>arr.length || c<0 || c>arr.length){
    				  return false;
    			  }
    			  else if(endFound(arr,r,c)==true){
    				  //else if(maze[r][c]=='*'){
    					  System.out.println("FINISHED!");
    					  for(int i=0;i!=arr.length;i++){
    						  System.out.println(arr[i]);
    					  }
    					  return true;
    				  }
    			  else if(maze[r][c]=='#'){
    				  return false;
    			  }
    			  else if(maze[r][c]!=' '){
    				  return false;
    			  }
    			  else{
    				  maze[r][c] = pathMarker;
    				  pathMarker++;
    				  ndx++;
    				  if(ndx==26){
    					  pathMarker='a';
    					  ndx=0;
    				  }
    				  if(findPath(arr,r+1,c)){
    					  return true;
    				  }else if(findPath(arr,r,c+1)){
    					  return true;
    				  }else if(findPath(arr,r,c-1)){
    					  return true;
    				  }else if(findPath(arr,r-1,c)){
    					  return true;
    				  }else{
    					  //maze[r][c]=' ';
    					  return false;  
    				  }
    	  }
    	  }
    }
    I don't know why, but when It is run it prints out the maze with every blank filled with letters. It does not stop at the '*' like it is suppose to. Am I just missing something or do I have a coding error?
    Last edited by sman1234; October 28th, 2010 at 12:00 PM.


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