python经典例题（持续更新）

1.打印9*9乘法表

for i in range(1, 10):
    for j in range(1, 10):
        print(j, "x", i, "=", i * j, "\t", end="")
        if i == j:
            print()
            break
       
 
for i in range(1,10):
    for j in range(1,i+1):
        print('%s*%s=%s'%(i,j,i*j),end=' ')
    print()


print ("\n".join("\t".join(["%s*%s=%s" %(x,y,x*y) \
            for y in range(1, x+1)]) for x in range(1, 10)))

2.# 要求用户输入总资产，例如:2000 显示商品列表，让用户根据序号选择商品，

# 加入购物车 购买，如果商品总额大于总资产，提示账户余额不足，否则，购买成功。

goods = [
    {"name": "电脑", "price": 1999},
    {"name": "鼠标", "price": 10},
    {"name": "游艇", "price": 20},
    {"name": "美女", "price": 998},
]

shopping = []
salary = input("your salary:").strip()
if salary.isdigit():
    salary = int(salary)
    print("以下是商品列表：")
    for index, item in enumerate(goods):
            print(index, item['name'], item['price'])

    while True:
        choice = input('what you want to buy:').strip()
        choice = int(choice)
        if (choice >= 0) and (choice < len(goods)):
            salary -= int(goods[choice]['price'])
            shopping.append((goods[choice]['name']))
            print('你所购买商品：%s' % goods[choice]['name'])
            print('你所剩余额：%s' % salary)
            if salary < int(goods[choice]['price']):
                print('你的余额已经不足以购买该商品')
                print('一下是你所购买的商品清单：', '\n', shopping)
                exit()
            else:
                continue
        else:
            print('你输入有误，请重新输入选择序号')
else:
    print('你输入有误，请重新输入选择序号')

3.斐波那契数列各种写法：

i, j = 0, 1
while i < 10000:
    print(i,end='\t')
    i, j = j, i+j

 

fibs = [0,1]
for i in range(100):
    fibs.append(fibs[-1] + fibs[-2])
print(fibs)

 

class Fib:
    def __init__(self,n = 10):
        self.a = 0
        self.b = 1
        self.n = n
    def __iter__(self):
        return self
    def __next__(self):
        self.a, self.b = self.b, self.a + self.b
        if self.a > self.n:
            raise StopIteration
        return self.a
f = Fib(100)
for i in f:
        print(i)

 4.三级菜单

dic = {
    "河北":{
        "石家庄" :{'bei':66},
        "邯郸" :{}
    },
    "河南":{
        "郑州":{},
        "开封":{}
    }
}

lis = []
while True:
    for k in dic:
        print(k)
    choice = input('>>>')
    if not choice:continue
    if choice in dic:
        lis.append(dic)
        dic = dic[choice]
    elif choice == 'q':
        if len(lis) != 0:
            dic = lis.pop()
        else:
            print('顶层啦')