Python | Find missing elements in List

Sometimes, we can get elements in range as input but some values are missing in otherwise consecutive range. We might have a use case in which we need to get all the missing elements. Let’s discuss certain ways in which this can be done.

Method #1 : Using list comprehension
We can perform the task of finding missing elements using the range function to get the maximum element fill and then insert the elements if there is a miss.

filter_none

edit
close

play_arrow

link
brightness_4
code

# Python3 code to demonstrate
# Finding missing elements in List
# using list comprehension
  
# initializing list
test_list = [3, 5, 6, 8, 10]
  
# printing original list
print("The original list : " + str(test_list))
  
# using list comprehension
# Finding missing elements in List
res = [ele for ele in range(max(test_list)+1) if ele not in test_list]
  
# print result
print("The list of missing elements : " + str(res))

chevron_right


Output :



The original list : [3, 5, 6, 8, 10]
The list of missing elements : [0, 1, 2, 4, 7, 9]

 

Method #2 : Using set()
This problem can also be performed using the properties of difference of set and then getting the elements that are missing in a range.

filter_none

edit
close

play_arrow

link
brightness_4
code

# Python3 code to demonstrate
# Finding missing elements in List
# Using set()
  
# initializing list
test_list = [3, 5, 6, 8, 10]
  
# printing original list
print("The original list : " + str(test_list))
  
# Using set()
# Finding missing elements in List
res = list(set(range(max(test_list) + 1)) - set(test_list))
  
# print result
print("The list of missing elements : " + str(res))

chevron_right


Output :

The original list : [3, 5, 6, 8, 10]
The list of missing elements : [0, 1, 2, 4, 7, 9]


My Personal Notes arrow_drop_up

Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.



Improved By : Akanksha_Rai



Article Tags :

Be the First to upvote.


Please write to us at contribute@geeksforgeeks.org to report any issue with the above content.