def bfs(g,start):
    start.setDistance(0)
    start.setPred(None)
    vertQueue = Queue()
    vertQueue.enqueue(start)
    while (vertQueue.start() > 0):
        currentVert = vertQueue.dequeue()
        for nbr in currentVert.getconnections():
            if (nbr.getcolor() == 'white'):
                nbr.setColor('gray')
                nbr.setDistance(currentVert.getDistance() + 1)
                nbr.setPred(currentVert)
                vertQueue.enqueue(nbr)
        currentVert.setColor('black')