编辑代码

# coding:utf-8
from math import *
print("n选a乐透分布")
while(True):
    n=eval(input("n="))
    b=eval(input("a="))
    if (n>b):
        break
    else:
        print("n要大于a!")
p=list(range(b+1))
for i in range(b):
    p[i]=comb(b,i)*perm(n-b,b-i)/perm(b-i,b-i)
p[b]=1
for i in range(b+1):
    print("中",i,"个的概率为",p[i]/comb(n,b),sep='')