2_列表和元组

names = ["zhangSan","liSi","wangWu","xinHua"]    
print(names)    #['zhangSan', 'liSi', 'wangWu', 'xinHua']
print(names[0])    #zhangSan
print(names[0],names[2])    #zhangSan wangWu
print(names[1:3])    #['liSi', 'wangWu']     切片  起始位置包括，结束位置不包括，顾头不顾尾
print(names[-1])    #xinHua    -1取最后一个
#想取后两个值
print(names[-1:-3])    #[] 取不出来
print(names[-3:-1])    #['liSi', 'wangWu']
print(names[-2:-1])    #['wangWu']
print(names[-2:])    #['wangWu', 'xinHua']

#追加变量
names = ["zhangSan","liSi","wangWu","xinHua"]
names.append("ziDian")
print(names)

#插入变量
names = ["zhangSan","liSi","wangWu","xinHua"]
names.append("ziDian")
names.insert(1,"xiaoMing")    #1是下标，插入到哪里写哪下标
print(names)
#不能批量插入，只能一个一个来

#改变量
names[1] = xiaoHong    #提对应修改变量的下标

#两种删除方法
del names[1]
names.remove("xiaoHong")

#特殊删除
names.pop()    #默认不输入下标的情况下删除最后一个，如果输入了下标删除对应下标的变量

#索引
print(names.index("xiaoHong"))    #会返回它对应的下标
print(names[names.index("xiaoHong")])    #使用names中括号，打印的不再是下标值，打印出的是名字

#统计列表内重名
names = ["zhangSan","liSi","wangWu","xinHua"]
names.append("liSi")
print(names)    #['zhangSan', 'liSi', 'wangWu', 'xinHua', 'liSi']
print(names.count("liSi"))    #2

#清空
names.clear()

#反转
names.reverse()

#排序
names.sort()    #特殊字符>数字>大写>小写

#合并
names2=[1,2,3,4]
names.extend(names2)
print(names,names2)    #['zhangSan', 'liSi', 'wangWu', 'xinHua', 1, 2, 3, 4] [1, 2, 3, 4]

#复制
names2 = names.copy()
print(names)
print(names2)

names = ["zhangSan","liSi","wangWu","xinHua"]
names2 = names.copy()
names[1] = "李四"
print(names)    #['zhangSan', '李四',"wangWu",'xinHua']
print(names2)    #['zhangSan', 'liSi', 'wangWu', 'xinHua']

#列表内包含子列表
names = ["zhangSan","liSi","wangWu",["ziDian","xiaoMing"],"xinHua"]    #["ziDian","xiaoMing"]这个子列表是names里的一个元素

#浅copy
names = ["zhangSan","liSi","wangWu",["ziDian","xiaoMing"],"xinHua"]
names2 = names.copy()
print(names)    #['zhangSan', 'liSi', 'wangWu', ['ziDian', 'xiaoMing'], 'xinHua']
print(names2)    #['zhangSan', 'liSi', 'wangWu', ['ziDian', 'xiaoMing'], 'xinHua']
names[1] = "李四"
names[3][0] = "字典"
print(names)    #['zhangSan', '李四', 'wangWu', ['字典', 'xiaoMing'], 'xinHua']
print(names2)    #['zhangSan', 'liSi', 'wangWu', ['字典', 'xiaoMing'], 'xinHua']
#copy不是完全克隆，是浅copy，只copy一层，机制是内存这么设定的，copy的是地址

#深copy
import copy
names = ["zhangSan","liSi","wangWu",["ziDian","xiaoMing"],"xinHua"]
names2 = copy.deepcopy(names)
print(names)    
print(names2)    
names[1] = "李四"
names[3][0] = "字典"
print(names)    #['zhangSan', '李四', 'wangWu', ['字典', 'xiaoMing'], 'xinHua']
print(names2)    #['zhangSan', 'liSi', 'wangWu', ['ziDian', 'xiaoMing'], 'xinHua']



补充：浅copy
import copy
person=['name'['a',100]]
#三种浅copy
p1=copy.copy(person    #引用
p2=person[:]    #完全切片
p3=list(person)    #工厂函数list

import copy
person=['name'['saving',100]]
p1=person[:]
p2=person[:]
p1[0]='a'
p2[0]='b'
print(p1)    #['a', ['saving', 100]]
prent(p2)    #['b', ['saving', 100]]


联合账号
import copy
person=['name',['saving',100]]
p1=person[:]
p2=person[:]
p1[0]='a'
p2[0]='b'

p1[1][1]=50

print(p1)    #['a', ['saving', 50]]
print(p2)    #['b', ['saving', 50]]


元组跟列表差不多，也是存一组数，只是它一旦创建，便不能再修改，所以又叫只读列表
它只有两个办法，一个是count，一个是index
语法：name = ("a","b","c")



程序练习

请闭眼写出以下程序。

程序：购物车程序

需求:

1、启动程序后，让用户输入工资，然后打印商品列表
2、允许用户根据商品编号购买商品
3、用户选择商品后，检测余额是否够，够就直接扣款，不够就提醒
4、可随时退出，退出时，打印已购买商品和余额

#我写的时候也是没思路，大王说得对，没思路，不会写就是代码写得少，无从下手

product_list=[
    ('Iphone',5800),
    ('Mac Pro',9800),
    ('Bick ',800),
    ('Watch',10600),
    ('Coffee',31),
    ('book',120)
]
shopping_list = []
salary = input("Input your salary:")    #输入工资
if salary.isdigit():    #判断工资是不是数字
    salary = int(salary)    #如果是数字给它int
    '''
    while True:
        for item in product_list:
            print(product_list.index(item),item)   #通过下标找
        break
    '''
    while True: #进入一个死循环
        for index,item in enumerate(product_list):
            print(index,item)   #打印商品列表
        user_chois = input("选择要买什么? >>>:")  #让用户选择买什么东西
        if user_chois.isdigit():    #判断用户输入必须是数字类型
            user_chois = int(user_chois)
            if user_chois < len(product_list) and user_chois >= 0:  #判断一下下标，避免出错
                p_item = product_list[user_chois]   #通过下标把商品取出来
                if p_item[1] <= salary: #判断是否买得起
                    shopping_list.append(p_item)    #添加到之前创建的空列表里
                    salary -= p_item[1] #扣钱
                    print("Added %s into shopping cart,your current balane is 33[31;1m%s33[0m"%(p_item,salary))
                else:
                    print("33[41;1m你的余额只剩%s了33[0m"%salary)
            else:
                print("product code [%s] is not exist"%user_chois)  #输入的商品序号不存在
        elif user_chois == 'q':#输入q退出
            print('---shopping list---')
            for p in shopping_list:
                print(p)    #打印购买的商品
            print("Your current balance:",salary)
            exit()
        else:
            print("invalid option")

 '''
enumerate作用
a=[1,2,3]
for i in enumerate(a):
print(i)

输出结果为：
(0, 1)
(1, 2)
(2, 3)
enumerate作用是把列表的下标取出来
'''