def BFS_dist(sink, distList):
    """
        returns the distance to sink given distList. Assumes source is distList[0]
        returns 1 more than length of distlist if sink not found in distlist
    """
    for i in range(len(distList)):
        if sink in distList[i]:
            return i
    
    ###else
    return len(distList) + 1