Rat in a Maze

RatInAMaze.py

#!/usr/bin/env python3
'''This code should actually work with any ASCII maze that contains spaces for open paths, and a S, and E for 
start and ending points. characters representing borders are redundant. 

Create a text file containing the maze and type the name of the file as input
while running this code.
'''

'''
Main method in which the program starts
'''
def main():
    location = [] #list to hold the location we are at in the maze
    hasNoEnd = True
    
    mazefile = input("What maze do you want solved?: ")
    maze = slurp(mazefile)
    for y in range(0, len(maze)):
        for x in range(0, len(maze[y])):
            if maze[y][x] == 'S':
                location = [y, x]
            elif maze[y][x] == 'E':
                hasNoEnd = False
    if len(location) == 0:
        raise Exception("No start cell found, check your input file")
    if hasNoEnd:
        raise Exception("Maze has no end, unsolvable.")
    
    tick(maze, location[0], location[1])
    print("\n\n")
    dump(maze)
    
'''
Loads the maze file into a matrix and returns it.
@param mazefile: Location of maze file
'''
def slurp(mazefile):
    infile = open(mazefile, 'r')
    #Split the maze into a matrix.
    maze = [list(row) for row in infile.read().splitlines()] #this line is beautiful. python is definately a powerful language.
    infile.close()
    
    return maze

'''
Prints the loaded maze matrix into a human readable format.
@param maze: Loaded maze matrix.
'''
def dump(maze):
    print('\n'.join(''.join(row) for row in maze)) #I had fun writing this too :P
    
'''
Recursive method which solves the maze.
@param maze: the maze matrix
@param y: the y location
@param x: the x location
'''
def tick(maze, y, x):
    dump(maze)
    print("\n")
    if maze[y][x] in (' ', 'S'):
        maze[y][x] = 'x'
        #check right, down, left, up
        if (tick(maze, y, x+1) or tick(maze, y-1, x) or 
            tick(maze, y, x-1) or tick(maze, y+1, x)):
            maze[y][x] = '.'
            return True
    elif maze[y][x] == 'E':
        return True #start peeling back.
    return False
        
'''
Start the main method if this program is run as main.
'''
if __name__ == "__main__":
    main()