python基础代码（猜年龄、从最内层跳出多层循环、简单的购物车程序）

1、猜年龄 ， 可以让用户最多猜三次！

age = 55
i=0
while i<3:
    user_guess = int (input ("input your guess:"))
    if user_guess > age:
        print ("try smaller ")

    elif user_guess < age:
        print ("try bigger")
    else :
        print ("you got it")
        break
    i += 1

　　

　　

2、猜年龄 ，每隔3次，问他一下，还想不想继续玩，y,n

age = 55
i=0
while i<3:
    user_guess = int (input ("input your guess:"))
    if user_guess > age:
        print ("try smaller ")

    elif user_guess < age:
        print ("try bigger")
    else :
        print ("you got it")
        break
    i += 1
    print(i)
    if i % 3 == 0:
        y_or_n= input("will continue? 'y' or 'n':")
        if y_or_n == 'y':
            i=0
        elif y_or_n == 'n':
            break

3、跳出多层循环，调用函数

方法一：

break_flag = False
for i in range(5):
    print ("爷爷层",i)
    for j in range(5):
        print("爸爸层",j)
        if i ==3:
            break_flag = True
            break
        for k in range(5):
            print ("孙子层",k)
            if k ==2:
                break_flag = True
                break
        if break_flag :
            break
    if break_flag :
        print ("我出来了")
        break

　　方法二：

break_flag = False
count = 0
while break_flag == False:
    print("爷爷层")
    while break_flag == False:
        print("爸爸层")
        while break_flag == False:
            count +=1
            if count >5:
                print ("孙子层")
                break_flag = True
print ("我出来了")

　　

 方法三：

跳出多层循环：（调用函数）
def work():
    for i in range(5):
	    for j in range(5):
		    for k in range(5):
			    if i == j == k == 2:
			       return i,j,k
			    else:
				    print(i, '----', j, '----', k)

print (work())

4、购物车程序：

功能要求：
    要求用户输入总资产，例如：50
    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。
    附加：可充值、某商品移除购物车
"""
"""
1.创建空的购物车列表
2.要求用户输入金额资产
3.输入后列出商品列表
4.用户选择商品，加入购物车
5.结算，如果商品价格大于用户总资产提示余额不足，询问是否删除商品
6.结算资金充裕，提示购买成功，显示余额并退出

 展示一：

while True:
    print("num\t\tgoods\t\tprices")
    for i in range(len(goods)):
        print(i + 1, ".\t\t", goods[i], "\t\t", prices[i])
    print("q .\t\tquit")
    num1 = input("请输入需要的物品编号：")
    if num1 == 'q':
        if len(goods_buy) != 0:
            print("您购买的商品是:")
        for j in range(len(goods)):
            count1 = goods_buy.count(goods[j])
            if count1 > 0:
                print(goods[j], prices[j] * count1)
        print("您还有 %d" % (salary))
        print("bye bye")
        break
    else:
        num=int(num1)

    if (num - 1) in range(len(goods)) and salary < prices[num - 1]:
        print("买不起,还差 %d " % (prices[num - 1] - salary))
    elif (num - 1) in range(len(goods)) and salary >= prices[num - 1]:
        salary = salary - prices[num - 1]
        goods_buy.append(goods[num - 1])
        print("放入购物车,扣钱,余额为 %d" % (salary))
    else:
        print("请输入商品列表中的标号")

展示二：

product_list = [['Iphone7',5800],
                ['Coffee',30],
                ['疙瘩汤',10],
                ['Python Book',99],
                ['Bike',199],
                ['ViVo X9',2499],
              ]

shopping_cart = []
salary = int(input("请输入你的工资:"))
while True:
    num = 0
    for product in product_list:
        print(num,product)
        num += 1
    choice = input("请输入您所选的商品编号：").strip()
    if choice.isdigit():
        choice = int(choice)
        if choice >= 0 and choice < len(product_list):
            product = product_list[choice]
            if product[1] <= salary:
                shopping_cart.append(product)
                salary = salary - product[1]
                print ("物品"+product[0]+"已经加入购物车","您的金额还剩："+str(salary -product[1]) + ' 元')
            else:
                print("余额不足，"+"还差："+str(product[1]-salary)+"元")
        else:
            print ("商品不存在")
    elif choice == "q":
        print ("已经购买的商品有：")
        for i in shopping_cart:
            print (i)

        print ("您的余额为：",salary)
        print("end")
        break
    else:
        print ("无此选项！")