leftturn.py

from collections import deque

def solve(maze):

	path = deque([maze.start])

	current = maze.start.Neighbours[2]

	if current == None:
		return path

	heading = 2 # South

	turn = 1 # Turning left, -1 for right

	startpos = maze.start.Position
	endpos = maze.end.Position

	# N E S W - just a helpful reminder
	# 0 1 2 3

	count = 1

	completed = False


	while True:
		path.append(current)
		count += 1
		position = current.Position
		if position == startpos or position == endpos:
			if position == endpos:
				completed = True
			break

		n = current.Neighbours

		if n[(heading - turn) % 4] != None:
			heading = (heading - turn) % 4
			current = n[heading]
			continue

		if n[heading] != None:
			current = n[heading]
			continue

		if n[(heading + turn) % 4] != None:
			heading = (heading + turn) % 4
			current = n[heading]
			continue

		if n[(heading + 2) % 4] != None:
			heading = (heading + 2) % 4
			current = n[heading]
			continue

		completed = False
		break

	return [path, [count, len(path), completed]]