Python | Check for Nth index existence in list Last Updated : 24 Mar, 2023 Comments Improve Suggest changes Like Article Like Report Sometimes, while working with lists, we can have a problem in which we require to insert a particular element at an index. But, before that it is essential to know that particular index is part of list or not. Let's discuss certain shorthands that can perform this task error free. Method #1 : Using len() This task can be performed easily by finding the length of list using len(). We can check if the desired index is smaller than length which would prove it's existence. Python3 # Python3 code to demonstrate working of # Check for Nth index existence in list # Using len() # initializing list test_list = [4, 5, 6, 7, 10] # printing original list print("The original list is : " + str(test_list)) # initializing N N = 6 # Check for Nth index existence in list # Using len() res = len(test_list) >= N # printing result print("Is Nth index available? : " + str(res)) Output : The original list is : [4, 5, 6, 7, 10] Is Nth index available? : False Time Complexity : O(n) Auxiliary Space : O(n), where n is length of list. Method #2 : Using try-except block + IndexError exception This task can also be solved using the try except block which raises a IndexError exception if we try to access an index not a part of list i.e out of bound. Python3 # Python3 code to demonstrate working of # Check for Nth index existence in list # Using try-except block + IndexError exception # initializing list test_list = [4, 5, 6, 7, 10] # printing original list print("The original list is : " + str(test_list)) # initializing N N = 6 # Check for Nth index existence in list # Using try-except block + IndexError exception try: val = test_list[N] res = True except IndexError: res = False # printing result print("Is Nth index available? : " + str(res)) Output : The original list is : [4, 5, 6, 7, 10] Is Nth index available? : False Time Complexity: O(n*n) where n is the length of the listAuxiliary Space: O(1), constant extra space is required Method#3: using the in operator Python3 # initializing list test_list = [4, 5, 6, 7, 10] # printing original list print("The original list is : " + str(test_list)) # initializing N N = 6 # Check for Nth index existence in list # Using the in operator res = N in range(len(test_list)) # printing result print("Is Nth index available? : " + str(res)) #This code is contributed by Vinay Pinjala. OutputThe original list is : [4, 5, 6, 7, 10] Is Nth index available? : False Time Complexity: O(n) Auxiliary Space: O(1) Comment More infoAdvertise with us Next Article Python | Check for Nth index existence in list manjeet_04 Follow Improve Article Tags : Python Python Programs Python list-programs Practice Tags : python Similar Reads How to Check if an Index Exists in Python Lists When working with lists in Python, sometimes we need to check if a particular index exists. This is important because if we try to access an index that is out of range, we will get an error. Let's look at some simple ways to check if an index exists in a Python list.The easiest methods to check if g 2 min read Python | Check if a list exists in given list of lists Given a list of lists, the task is to check if a list exists in given list of lists. 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