-----元组-----
元组查询
1 a = (1,2,3,4)
2 print(a[1:2]) #(2,)
购物车练习(列表方法练习)
1 product_list=[
2 ['Mac',9000],
3 ['kindle',800],
4 ['tesla',900000],
5 ['python book',105],
6 ['bike',2000],
7 ]
8 pubs_list = []
9 save = input("please input money:")
10 if save.isdigit():
11 save = int(save)
12 while True:
13
14 print("shopping info".center(50,"-"))
15 #、打印商品内容
16 for i,v in enumerate(product_list,1):
17 print(i,v)
18 choice = input("please input nums:")
19 #验证输入是否合法
20 if choice.isdigit():
21 choice = int(choice)
22 if choice > 0 and choice <= len(product_list):
23 #将用户选择商品用p_iters取出
24 p_iters = product_list[choice-1]
25 # print(p_iters)
26 #如果剩余钱足够,可以继续购买
27 if p_iters[1] < save:
28 pubs_list.append(p_iters)
29 print(p_iters)
30 save -= p_iters[1]
31 else:
32 print("余额不足 %s" % save)
33 elif choice == 'quit':
34 for j in pubs_list:
35 # print(pubs_list)
36 print("您购买的商品 :%s" % j)
37 print("购买商品剩余金额 :%s" % save)
38 break
39
40 else:
41 print("Invalid input")
View Code
-----字典-----
字典:是Python中唯一的映射类型,采用键值对的形式存储数据。
特点:1、字典是无序的,且键(key)可哈希 2、键唯一
不可变类型:整型,字符串,元祖
可变类型:列表,字典
字典的创建
1 a=list() #列表创建
2 print(a) #[]
3
4 dic={'name':'dream'}
5 print(dic) #{'name': 'dream'}
6
7 dic1={}
8 print(dic1) #{}
9
10 dic2=dict((('name','dream'),))
11 print(dic2) #{'name': 'dream'}
12
13 dic3=dict([['name','dream'],])
14 print(dic3) #{'name': 'dream'}
id方法使用
1 a = 100
2 print(id(a)) #94845938306592
3 b = a
4 print(id(b)) #94845938306592
5 b = 20
6 print(id(b)) #94457323938848
字典增加
1 dic1 = {'name':'dream'}
2 print(dic1) #{'name': 'dream'}
3 #setdefault,键存在,返回想用的键相应的值;,键不存在,在字典中添加新的键值对
4 ret = dic1.setdefault('age',20)
5 print(dic1) #{'name': 'dream', 'age': 20}
6 print(ret) #20
字典的查询
1 dic2 = {'age': 20, 'name': 'dream'}
2 print(dic2['name']) #dream
显示列表中所有的键
1 print(dic2.keys()) #dict_keys(['age', 'name'])
2 print(list(dic2.keys())) #['name', 'age']
3 #显示列表中说有的值
4 print(list(dic2.values())) #[20, 'dream']
5 #显示列表中说有的键、值
6 print(list(dic2.items())) #[('name', 'dream'), ('age', 20)]
字典修改
1 dic3 = {'age': 20, 'name': 'dream'}
2 dic3['name'] = 'rise'
3 print(dic3) #{'name': 'rise', 'age': 20}
4 #update
5 dic4 = {'age':18,'sex':'man'}
6 dic3.update(dic4)
7 print(dic3) #{'age': 18, 'sex': 'man', 'name': 'rise'}
字典删除
1 dic5 = {'age': 18, 'sex': 'man', 'name': 'rise'}
2
3 #del 删除键值对
4 del dic5['age']
5 print(dic5) #{'sex': 'man', 'name': 'rise'}
6 #clear 清空字典
7 dic5.clear()
8 print(dic5) #{}
9
10 #pop 删除字典中指定键值对,并返回该键值对的值
11 ret = dic5.pop('name')
12 print(ret) #rise
13 print(dic5) #{'sex': 'man', 'age': 18}
14 #popitem 随机删除某组键值对,病以元祖方式返回值
15 ret = dic5.popitem()
16 print(ret) #('sex', 'man')
17 print(dic5) #{'name': 'rise', 'age': 18}
18 #删除整个字典
19 del dic5
20 print(dic5)
字典初始化
1 dic6 = dict.fromkeys(['age', 'sex','name','rise'],'test')
2 print(dic6) #{'rise': 'test', 'sex': 'test', 'age': 'test', 'name': 'test'}
字典嵌套
1 school = {
2 "teachers":{
3 'xiaowang':["高个子","长的帅"],
4 'xiaohu':["技术好","玩的好"]
5 },
6 "students":{
7 "zhangsan":["成绩好","爱讲笑话"]
8 }
9 }
字典嵌套