Python list list and set set operations

The following are some basic operations of python's list and set

1. Some operations of list

list = [1, 2, 3]
list.append(5)
print(list)

list.extend([ 7 , 8 ])   # extend is to add the elements of the iterable object to the list in turn
 print (list)

list.append([ 7 , 8 ])   # append is to add the incoming parameter as an element to the list
 print (list)

list.reverse() #Elements   are reversed. Note that this operation cannot be assigned to a variable. This operation is an operation on the list itself, that is, the list itself changes
 . # l=list.reverse() l is empty, and the reversed list is not obtained. value
 print (list)

Output result:

2.set basic operation

list = [1, 1, 3, 2, 3]
s = set(list)
print(s)

s.add( 4 )
 # s.add([2,3]) error, the add function can only add elements of the same type as the original set
 print (s)

s.update([ 3 , 5 , 6 ])
 # s.update(5) error, an iterable object is passed in when
 update updates the collection print (s)

c = s.copy() #For   collection copy , create a new collection
 cc = s
 print (c)
 print (cc)
 #Similar to the copy method
 in list print (cc is c)

ss = {1, 2, 3, 9}
minus = s.difference(ss) #find the   difference print
 ( minus)

union = s.union(ss) #Union   print ( union
 )

intersection = s.intersection(ss) #Seek   intersection print
 ( intersection)

Output result: