python实现 深度优先算法

python 小程序，实现简单的dfs算法

    from game import Directions
    from util import Stack
    stack = Stack()
    fatherStack = Stack()
    moveDir = []    # record  the pacman move direction
    result = []        # the correct lines
    temp = {}
    startState = problem.getStartState() #  start the position 
    moveStart = [startState, Directions.STOP, 0]
    stack.push(moveStart)
    fatherStack.push(moveStart)
    flag = False
    while True:
        if  stack.isEmpty():
            print "can not find food"
        if flag==False:
            mo