In this article, we will discuss how to check if a set contains an element in python.
Method: 1 Using in operator
This is an membership operator used to check whether the given value is present in set or not. It will return True if the given element is present in set , otherwise False.
Syntax:
element in set
where
- set is an input set
- element is the value to be checked
Example: Check if an element is present in a set
Python3
# import random module import random # create a set with integer elements data = { 7058 , 7059 , 7072 , 7074 , 7076 } # check 7058 print ( 7058 in data) # check 7059 print ( 7059 in data) # check 7071 print ( 7071 in data) |
Output:
True True False
Method 2: Using not in operator
This is an membership operator used to check whether the given value is present in set or not. It will return True if the given element is not present in set, otherwise False
Syntax:
element not in set
where,
- set is an input set
- element is the value to be checked
Example: Check if an element is present in a set
Python3
# import random module import random # create a set with integer elements data = { 7058 , 7059 , 7072 , 7074 , 7076 } # check 7058 print ( 7058 not in data) # check 7059 print ( 7059 not in data) # check 7071 print ( 7071 not in data) |
Output:
False False True
Method 3: Using Counter() Function
Python3
from collections import Counter # create a set with integer elements data = { 7058 , 7059 , 7072 , 7074 , 7076 } freq = Counter(data) # check 7058 print ( 7058 in freq.keys()) # check 7059 print ( 7059 in freq.keys()) # check 7071 print ( 7071 in freq.keys()) |
True True False
Time Complexity:O(N)
Auxiliary Space: O(N)
Method #4 : Using operator.countOf() method.
Python3
import operator as op # create a set with integer elements data = { 7058 , 7059 , 7072 , 7074 , 7076 } # check 7058 print (op.countOf(data, 7058 ) > 0 ) # check 7059 print (op.countOf(data, 7059 ) > 0 ) # check 7071 print (op.countOf(data, 7071 ) > 0 ) |
True True False
Time Complexity: O(n)
Auxiliary Space: O(1)