the day of python learning(字典)

#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:元祖,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
"""
dic1 = {"age":18, "name":'ren','sex':'male'}
#字典的增加
#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)

#字典的删除
# 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)#会报错
# del dic1
# print(dic1)
#
# dic1.clear()#清空字典

#字典的修改
# dic1['age'] = 16
# dic = {'name':'jin','age': 18, 'sex':'male'}
# dic2 = {'name':'alex','weight':75}
# dic2.update(dic)
# print(dic)
# print(dic2)

#字典的查找
# 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)
#结果一样,直接for i in dic1:

# 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]
# 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'))

#字典的嵌套
# dic = {
# 'name':['alex','wusir','taibai'],
# 'py9':{
# 'time':'1213',
# 'learn_money':19800,
# 'addr':'CBD'
# },
# 'age':21
# }
# dic['age'] = 56
# print(dic['name'])
# dic['name'].append('renxin')
# print(dic)
# l = [1,2,'wusir']
# l[2] = l[2].upper()
# dic['name'][1] = dic['name'][1].upper()
# print(dic)
#
#
# """female:6"""
# dic['py9']['female'] = 6
# print(dic)



#输入一组数字。将其打印出数字的个数,包括连接的整数
info = input('>>>').strip()
for i in info:
if i.isalpha():
info = info.replace(i," ")
l = info.split()
print(len(l))
 
原文地址:https://www.cnblogs.com/wai-xin-ren/p/9498503.html