Python 冒泡法排序

一. Python 冒泡法排序
def sequence(arrays=list()):

    def desc():
        for i in range(1, len(arrays)):
            for j in range(len(arrays) - i):
                if arrays[j] < arrays[j + 1]:
                    arrays[j], arrays[j + 1] = arrays[j + 1], arrays[j]
        return arrays

    def asc():
        for i in range(1, len(arrays)):
            for j in range(len(arrays) - i):
                if arrays[j] > arrays[j + 1]:
                    arrays[j], arrays[j + 1] = arrays[j + 1], arrays[j]
        return arrays

    print desc()
    print asc()

if __name__ == "__main__":

    sequence([1, 2, -1, 10, 12, 9, 13, 14])

二. 有1、2、3、4个数字，能组成多少个互不相同且无重复数字的三位数？都是多少？

def combinations():

    num = [1, 2, 3, 4]
　　 # 列表解析
    res = [i * 100 + j * 10 + k for i in num for j in num for k in num if(j != i and k != j and k != i)]

    print (res)

if __name__ == "__main__":

    combinations()

三、输出100以内的质数（大于1的且因数只有它自身与1的自然数）

def prime_num():

    count = 0

    for i in range(2, 100):

        for j in range(2, i):
            if i % j == 0:
                break
        else:
            print i,
            count += 1

    print
    print "total: " + str(count)

if __name__ == "__main__":

    prime_num()

四、打印九九乘法表

def multiplication_tables():

    for i in range(1, 10):
        print

        for j in range(1, i + 1):
            print "%d*%d=%d" % (i, j, i * j),

if __name__ == "__main__":

    multiplication_tables()

五、斐波那契数列
def recur_fibo(n):
   """递归函数
   输出斐波那契数列"""
   if n <= 1:
       return n
   else:
       return(recur_fibo(n-1) + recur_fibo(n-2))
 
# 获取用户输入
nterms = int(input("您要输出几项? "))
 
# 检查输入的数字是否正确
if nterms <= 0:
   print("输入正数")
else:
   print("斐波那契数列:")
   for i in range(nterms):
       print(recur_fibo(i))