Creating a maze solving algorithm in Java

Question

I\'ve been assigned with the task of creating a maze solver in Java. Here\'s the assignment:

Write an application that finds a path through a maze.  
The maze sh         


        

Answer 1

As amit has said, you should first read the entire maze and store it as a 2 dimensional array. This lets you see the whole maze without having to solve it line-by-line.

Since you'll first need to find the size of the array, you should read the text file into a List of Strings.

List strs = new ArrayList();

//Pseudocode, choose however you want to read the file
while(file_has_next_line) {
    strs.add(get_next_line);
}

The size of the List gives you the number of rows, and assuming it's always a grid, you can use split().length, (count spaces + 1) or count the symbols on any one of the Strings to get the number of columns.

Easiest way to store the map data is with a 2D array of booleans. Where true is a wall and false is empty space.

boolean[][] wallMap = new boolean[rows][cols];

for(int i = 0; i < wallMap.length; i++) {

    //Separate each symbol in corresponding line
    String[] rowSymbols = strs.get(i).split(" ");

    for(int j = 0; j < wallMap[i].length; j++) {

        //Ternary operator can be used here, I'm just keeping it simple
        if(rowSymbols[j].equals("X")) {
             wallMap[i][j] = true;
        } else {
             wallMap[i][j] = false;
        }

    }

}

Now that you have the map data stored in an array it's much easier to traverse the map and make your choices, you can either use a ready-made algorithm (see amit's answer) or make your own. As this is homework, you should try and think up your own.

Have fun.