循环，元组，字典，列表，代码整理

循环

# msg=‘hello‘# msg=[1,2,3,4,5,6]msg=(1,2,3,4,5,6)msg_dic={‘apple‘:10,‘tesla‘:1000000,‘mac‘:3000,‘lenovo‘:30000,‘chicken‘:10,}index=0while index < len(msg):    print(msg[index])    index+=1

msg=‘hello‘# msg=[‘a‘,‘b‘,‘c‘,‘d‘,‘e‘]# msg=(‘a‘,‘b‘,‘c‘,‘d‘,‘e‘)for i in range(len(msg)):    print(i,msg[i])

不依赖索引的取值for item in msg_dic:    print(item,msg_dic[item])msg=‘hello‘msg=[1,2,3,4,5,6]msg=(1,2,3,4,5,6)for item in msg:    print(item)补充range:顾头不顾尾，默认从0开始print(type(range(1,2)))for i in range(10):    print(i,type(i))for i in range(1,10,2):    print(i,type(i))for i in range(10,1,-2):    print(i)for i in range(1,10,1):    print(i)for i in range(9,0,-1):    print(i)breakcontinuefor i in range(10):    if i == 4:        # break        continue    print(i)for+elsefor i in range(10):    print(i)    breakelse:    print(‘===>‘)

元组

为何要有元组，存放多个值，元组不可变，更多的是用来做查询t=(1,[1,3],‘sss‘,(1,2)) #t=tuple((1,[1,3],‘sss‘,(1,2)))print(type(t))

#元组可以作为字典的keyd={(1,2,3):‘egon‘}print(d,type(d),d[(1,2,3)])　索引　　　　切片goods=(‘iphone‘,‘lenovo‘,‘sanxing‘,‘suoyi‘)print(goods[1:3])

　　　　长度

in:字符串:子字符串列表：元素元组：元素字典：key

goods=(‘iphone‘,‘lenovo‘,‘sanxing‘,‘suoyi‘)print(‘iphone‘ in goods)

d={‘a‘:1,‘b‘:2,‘c‘:3}print(‘b‘ in d)

掌握goods=(‘iphone‘,‘lenovo‘,‘sanxing‘,‘suoyi‘)print(goods.index(‘iphone‘))print(goods.count(‘iphone‘))

补充：元组本身是不可变的，但是内部的元素可以是可变类型t=(1,[‘a‘,‘b‘],‘sss‘,(1,2)) #t=tuple((1,[1,3],‘sss‘,(1,2)))

t[1][0]=‘A‘print(t)t[1]=‘aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa‘

字典

info=[‘egon‘,‘male‘,18,180,75]

info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}常用操作：

　　　　存/取info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}print(info_dic[‘name11111111‘])print(info_dic.get(‘name‘,None))

pop：key存在则弹出值，不存在则返回默认值，如果没有默认值则报错print(info_dic.pop(‘nam123123123123123123e‘,None))print(info_dic)

print(info_dic.popitem())print(info_dic)

info_dic[‘level‘]=10print(info_dic)　　　　删除info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}info_dic.pop()info_dic.popitem()

del info_dic[‘name‘]

　　　　键s，值s，键值对info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}print(info_dic.keys())print(info_dic.values())print(info_dic.items())

for k in info_dic:    # print(k,info_dic[k])    print(k)print(‘========>‘)for k in info_dic.keys():    print(k)for val in info_dic.values():    print(val)for k,v in info_dic.items(): #k,v=(‘name‘, ‘egon‘)    print(k,v)

　　　　长度info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}print(len(info_dic))

　　　　循环#　　　　包含in

info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}print(‘name‘ in info_dic)print(‘name‘ in info_dic.keys())print(‘egon‘ in info_dic.values())print((‘name‘,‘egon‘) in info_dic.items())

掌握info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}info_dic.update({‘a‘:1,‘name‘:‘Egon‘})print(info_dic)

info_dic[‘hobbies‘]=[]info_dic[‘hobbies‘].append(‘study‘)info_dic[‘hobbies‘].append(‘read‘)print(info_dic)

setdefault:key不存在则设置默认值，并且放回值默认值key存在则不设置默认，并且返回已经有的值

info_dic.setdefault(‘hobbies‘,[1,2])print(info_dic)info_dic.setdefault(‘hobbies‘,[1,2,3,4,5])print(info_dic)

info_dic={‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘}

{‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘,‘hobbies‘:[‘study‘]}info_dic.setdefault(‘hobbies‘,[]).append(‘study‘)

{‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘,‘hobbies‘:[‘study‘,‘read‘]}info_dic.setdefault(‘hobbies‘,[]).append(‘read‘)

{‘name‘:‘egon‘,‘age‘:18,‘sex‘:‘male‘,‘hobbies‘:[‘study‘,‘read‘,‘sleep‘]}info_dic.setdefault(‘hobbies‘,[]).append(‘sleep‘)l=info_dic.setdefault(‘hobbies‘,[])print(l,id(l))print(id(info_dic[‘hobbies‘]))

print(info_dic)

了解d=info_dic.copy()print(d)info_dic.clear()print(info_dic)

d=info_dic.fromkeys((‘name‘,‘age‘,‘sex‘),None)print(d)d1=dict.fromkeys((‘name‘,‘age‘,‘sex‘),None)d2=dict.fromkeys((‘name‘,‘age‘,‘sex‘),(‘egon‘,18,‘male‘))print(d1)print(d2)

info=dict(name=‘egon‘,age=18,sex=‘male‘)print(info)

info=dict([(‘name‘,‘egon‘),(‘age‘,18)])print(info)

列表

l=[1,2,3] #l=list([1,2,3])print(type(l))

pat1===》优先掌握部分　索引　　　　切片l=[‘a‘,‘b‘,‘c‘,‘d‘,‘e‘,‘f‘]

print(l[1:5])print(l[1:5:2])print(l[2:5])print(l[-1])

了解print(l[-1:-4])print(l[-4:])l=[‘a‘,‘b‘,‘c‘,‘d‘,‘e‘,‘f‘]print(l[-2:])

　　　　追加hobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘]hobbies.append(‘girls‘)print(hobbies)

　　　　删除hobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘]x=hobbies.pop(1) #不是单纯的删除，是删除并且把删除的元素返回，我们可以用一个变量名去接收该返回值print(x)print(hobbies)

x=hobbies.pop(0)print(x)

x=hobbies.pop(0)print(x)

队列：先进先出queue_l=[]#入队queue_l.append(‘first‘)queue_l.append(‘second‘)queue_l.append(‘third‘)print(queue_l)出队print(queue_l.pop(0))print(queue_l.pop(0))print(queue_l.pop(0))

堆栈:先进后出，后进先出l=[]#入栈l.append(‘first‘)l.append(‘second‘)l.append(‘third‘)#出栈print(l)print(l.pop())print(l.pop())print(l.pop())

了解del hobbies[1] #单纯的删除hobbies.remove(‘eat‘) #单纯的删除，并且是指定元素去删除　　　　长度hobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘]print(len(hobbies))

　　　　包含inhobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘]print(‘sleep‘ in hobbies)

msg=‘hello world egon‘print(‘egon‘ in msg)

#pat2===》掌握部分hobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘,‘eat‘,‘eat‘]hobbies.insert(1,‘walk‘)hobbies.insert(1,[‘walk1‘,‘walk2‘,‘walk3‘])print(hobbies)

print(hobbies.count(‘eat‘))print(hobbies)hobbies.extend([‘walk1‘,‘walk2‘,‘walk3‘])print(hobbies)

hobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘,‘eat‘,‘eat‘]print(hobbies.index(‘eat‘))

pat3===》了解部分hobbies=[‘play‘,‘eat‘,‘sleep‘,‘study‘,‘eat‘,‘eat‘]hobbies.clear()print(hobbies)

l=hobbies.copy()print(l)

l=[1,2,3,4,5]l.reverse()print(l)

l=[100,9,-2,11,32]l.sort(reverse=True)print(l)