In this program, I am trying to print a solution for the maze with '*' indicating a wall, ' ' indicating a corridor, and '#' indicating a solution path. I am using a recursive backtracking algorithm in this program. For instance, here is a small (8-by-12) maze:

8 12
  **********
* *        *
*   ****** *
*****      *
*     ******
*** ***    *
*       ** *
**********  

Here is the same maze printed showing the solution:

##**********
*#*########*
*###******#*
*****######*
*  ###******
***#***####*
*  #####**#*
**********##

Here is my code:

#include<iostream>
#include<fstream>
using namespace std;

#define MAXROW 24
#define MAXCOL 81

char a[MAXROW][MAXCOL];
int rows, columns;

void readMaze(ifstream &in)
{    
    in >> rows >> columns;
    cout << rows << " " << columns << endl;
    in.getline(a[0],sizeof a[0]);
    for(int i = 0; i < rows; i++)
    {
        in.getline(a[i], sizeof a[i]);    
    }
}

void printMaze()
{
    for(int i = 0; i < rows; i++)
    {
        cout << a[i] << endl;
    }
}

bool solveMaze(int rows, int columns)
{
    if(rows < 0 || rows > MAXCOL-1 || columns < 0 || columns > MAXROW-1)
    {
        return false;
    }
    if(a[columns][rows] == '*')
    {
        return false;
    }
    a[columns][rows] = '#';
    if(solveMaze(rows, columns-1))
    {
        return true;
    }
    if(solveMaze(rows+1, columns))
    {
        return true;
    }
    if(solveMaze(rows, columns+1))
    {
        return true;
    }
    if(solveMaze(rows-1, columns))
    {
        return true;
    }
    a[columns][rows] = 'x';
    return false;
}

int main()
{
    char inFile[20] = "maze.txt";
    ifstream in;
    int rows = 0, columns = 0;

    cout << "Enter file name: ";
    cin >> inFile;

    if(!inFile)
    {
        cout << "Error" << endl;
        return 1;
    }

    in.open(inFile);

    cout << "Maze before solve: " << endl;
    readMaze(in);
    printMaze();
    cout << "Maze after: " << endl;
    solveMaze(rows,columns);
    printMaze();
    in.close();
    return 0;
}

The only thing I am having trouble with is printing the solution path. I don't know what I am doing wrong in this program. There could be something wrong in the solveMaze() function. What do I need to change in this program in order to print the solution path?

Edited 3 Years Ago by andrew mendonca

In your PrintMaze function you need to print out the 2-D array of the maze. You are just printing out the rows.

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