复制代码 代码如下:

import random

def genrand(small, big) :

return small + (big-small) * random.random()

def display(small, big) :

return r'请输入上下限(默认%.2f~%.2f):' % (small, big)

big = 100

small = 0

while True :

try :

s = input(display(small, big)).strip()

if s.lower() == 'exit' :

break

a = s.split()

if a != [] :

big = float(a[1])

small = float(a[0])

rand = genrand(small, big)

print('(%.2f~%.2f): %.3fn' % (small, big, rand))

except :

print('--Error--n')