def str2float(s):    
    a, b = s.split('.')
    zs = reduce(lambda x, y: x * 10 + y, map(convert, a))
    xs = reduce(lambda x, y: x*0.1+y, map(convert, reversed(b)))
    return zs + xs*0.1

def convert(ite):
    dic = {'0': 0, '1': 1, '2': 2, '3': 3, '4': 4, '5': 5, '6': 6}
    return dic[ite]