Data structure of the Python language 1 (Sequence--list, tuple, string)

0. Sequence

Lists, tuples, strings are sequences.

There are two features of the sequence: index operator and slice operator. The index operator allows us to fetch a specific item from the sequence. The slice operator allows us to get a slice of the sequence, which is part of the sequence.

Take the string as an example:

 1 str= "01 3456 89?  "2 3 print (str[0]) #4 print (Str[1:5]) #< Span style= "color: #008000;" > ' 1 34 ', sliced 5 print (Str[5:1:-1]) # ' 543 ' 6 print (str[ 1:5:-1]) #output a ' \ n ', no error     

1. List

Common actions for lists:

1 fruitlist = [‘Lemon‘,‘Mango‘]2Print (Len (fruitlist),"Kinds of fruit" )#2 Kinds of fruit34For fruitInchFruitlist:5Print(fruit)67 Fruitlist.append ("Banana" )#fruitlist = [' Lemon ', ' mango ', ' banana '] 9 Fruitlist[0]= ' orange  ' #fruitlist = [' Orange ', ' Mango ']10 fruitlist.sort () fruitlist = [' banana ', ' orange ']            

Of course you can play the same way:

1 special_list = ["str", 1, ("Tuplea", 2), [3,4,5]]#Tuplea#5 

2. Tuples

Tuples and lists are very similar, except that tuples and strings are immutable. That is, you cannot modify tuples. The tuple is initialized in the following way:

1 fruittuple = ('lemon'mango'#empty tuple#tuple have only one element 

Note When initializing a tuple of an element, a comma is required after the unique element, indicating that a tuple is currently initialized instead of an object with parentheses.

Commonly used in print statements, and% cooperation to achieve custom string output.

3. String

Common String Operations:

1Smile ="~^_^~"2 ifSmile.startswith ("@[email protected]"):3     Print("It is fake smile")4 if "~" inchSmile:5     Print("Shy")6 ifSmile.find ("?")! =-1:7     Print("Is you confused?")8 9Alist = ["1","2","3"]TenJoinstr = Smile.join (alist)#joinstr = ' 1~ ^_^ ~2~ ^_^ ~ ' OneSplitlist = Joinstr.split ('~')#splitlist = [' 1 ', ' ^_^ ', ' 2 ', ' ^_^ ', ' 3 ']

Data structure of the Python language 1 (Sequence--list, tuple, string)