python实现计算组合数 C(n,m) 计算双色球组合数

[python]代码库

# 用python实现排列组合C(n,m) = n!/m!*(n-m)!

# 求阶乘，递归
def get_value(n):
    if n == 1:
        return n
    else:
        return n * get_value(n - 1)


# 求组合数
def gen_last_value(n, m):
    first = get_value(n)
    print("n:%s  value:%s" % (n, first))

    second = get_value(m)
    print("m:%s  value:%s" % (m, second))

    third = get_value((n - m))
    print("n-m:%s  value:%s" % ((n - m), third))

    return first / (second * third)


if __name__ == "__main__":
    # 双色球组合数
    # 红球33选6
    # 蓝球16选1
    rest = gen_last_value(33, 6) * gen_last_value(16, 1)
    print("双色球组合数:", rest)


输出：

n:33  value:8683317618811886495518194401280000000
m:6  value:720
n-m:27  value:10888869450418352160768000000
n:16  value:20922789888000
m:1  value:1
n-m:15  value:1307674368000
双色球组合数: 17721088.0