3.列表

列表

一、列表

　　作用：多个装备，多个爱好，多门课程，多个女朋友等

　　定义：[]内可以有多个任意类型的值，逗号分隔

以下是列表的常用操作：

 

  1 l=[1,2,3] #l=list([1,2,3])
  2 # print(type(l))
  3 
  4 #pat1===》优先掌握部分
  5 # 　索引：l=[1,2,3,4,5]
  6 　　　　　 print(l[0])  7 # 　切片
  8 l=['a','b','c','d','e','f']
  9 
 10 # print(l[1:5])
 11 # print(l[1:5:2])
 12 # print(l[2:5])
 13 # print(l[-1])
 14 
 15 
 16 #了解
 17 # print(l[-1:-4])
 18 # print(l[-4:])
 19 # l=['a','b','c','d','e','f']
 20 # print(l[-2:])
 21 
 22 # 　　追加
 23 # hobbies=['play','eat','sleep','study']
 24 # hobbies.append('girls')
 25 # print(hobbies)
 26 
 27 # 　　删除
 28 hobbies=['play','eat','sleep','study']
 29 # 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
 30 # print(x)
 31 # print(hobbies)
 32 
 33 # x=hobbies.pop(0)
 34 # print(x)
 35 #
 36 # x=hobbies.pop(0)
 37 # print(x)
 38 
 39 #队列：先进先出
 40 queue_l=[]
 41 #入队
 42 # queue_l.append('first')
 43 # queue_l.append('second')
 44 # queue_l.append('third')
 45 # print(queue_l)
 46 #出队
 47 # print(queue_l.pop(0))
 48 # print(queue_l.pop(0))
 49 # print(queue_l.pop(0))
 50 
 51 
 52 #堆栈:先进后出，后进先出
 53 # l=[]
 54 # #入栈
 55 # l.append('first')
 56 # l.append('second')
 57 # l.append('third')
 58 # #出栈
 59 # print(l)
 60 # print(l.pop())
 61 # print(l.pop())
 62 # print(l.pop())
 63 
 64 #了解
 65 # del hobbies[1] #单纯的删除
 66 # hobbies.remove('eat') #单纯的删除，并且是指定元素去删除
 67 
 68 
 69 # 　　长度
 70 # hobbies=['play','eat','sleep','study']
 71 # print(len(hobbies))
 72 
 73 # 　　包含in
 74 # hobbies=['play','eat','sleep','study']
 75 # print('sleep' in hobbies)
 76 
 77 # msg='hello world egon'
 78 # print('egon' in msg)
 79 
 80 
 81 ##pat2===》掌握部分
 82 hobbies=['play','eat','sleep','study','eat','eat']
 83 # hobbies.insert(1,'walk')
 84 # hobbies.insert(1,['walk1','walk2','walk3'])
 85 # print(hobbies)
 86 
 87 # print(hobbies.count('eat'))
 88 # print(hobbies)
 89 # hobbies.extend(['walk1','walk2','walk3'])
 90 # print(hobbies)
 91 
 92 hobbies=['play','eat','sleep','study','eat','eat']
 93 # print(hobbies.index('eat'))
 94 
 95 
 96 #pat3===》了解部分
 97 hobbies=['play','eat','sleep','study','eat','eat']
 98 # hobbies.clear()
 99 # print(hobbies)
100 
101 # l=hobbies.copy()
102 # print(l)
103 
104 # l=[1,2,3,4,5]
105 # l.reverse()
106 # print(l)
107 
108 l=[100,9,-2,11,32]
109 l.sort(reverse=True)
110 print(l)