dict
'''
#数据类型划分:可变数据类型,不可变数据类型
不可变数据类型:元组,bool int str 可哈希
可变数据类型:list,dict set 不可哈希
dict key 必须是不可变数据类型,可哈希,
value:任意数据类型。
dict 优点:二分查找去查询
存储大量的关系型数据
特点:无序的
'''
# dic = {
# 'name':['大猛','小孟'],
# 'py9':[{'num':71,'avg_age':18,},
# {'num': 71, 'avg_age': 18, },
# {'num': 71, 'avg_age': 18, },
# ],
# True:1,
# (1,2,3):'wuyiyi',
# 2:'二哥',
# }
# print(dic)
dic1 = {'age': 18, 'name': 'jin', 'sex': 'male',}
#增:
# dic1['high'] = 185 #没有键值对,添加
# dic1['age'] = 16 #如果有键,则值覆盖
# dic1.setdefault('weight') # 有键值对,不做任何改变,没有才添加。
# dic1.setdefault('weight',150)
# dic1.setdefault('name','二哥')
# print(dic1)
#删
# print(dic1.pop('age')) # 有返回值,按键去删除
# print(dic1.pop('二哥',None)) # 可设置返回值
# print(dic1)
# print(dic1.popitem()) # 随机删除 有返回值 元组里面是删除的键值。
# # print(dic1)
# del dic1['name1']
# print(dic1)
# del dic1
# print(dic1)
# dic1.clear() #清空字典
#改 update
# dic1['age'] = 16
# dic = {"name":"jin","age":18,"sex":"male"}
# dic2 = {"name":"alex","weight":75}
# dic2.update(dic) #
#
# print(dic)
# print(dic2)
dic1 = {'age': 18, 'name': 'jin', 'sex': 'male',}
#查
# print(dic1.keys(),type(dic1.keys()))
# print(dic1.values())
# print(dic1.items())
# for i in dic1:
# print(i)
# for i in dic1.keys():
# print(i)
# for i in dic1.values():
# print(i)
# a,b = 1,2
# print(a,b)
# a = 1
# b = 2
# a,b = b,a
# print(a,b)
# a,b = [1,2],[2,3]
# a,b = (1,2)
# print(a,b)
# for k,v in dic1.items():
# print(k,v)
# v1 = dic1['name']
# print(v1)
# v2 = dic1['name1'] # 报错
# print(v2)
# print(dic1.get('name1','没有这个键'))