Sometimes, while working with Python lists, we can have a problem or part of it, in which we desire to convert a list after deletion of some random element. This can have it’s application in gaming domain or personal projects. Let’s discuss certain way in which this task can be done.
Method : Using randrange() + pop() In this, we just combine the functionality of above functions into one and achieve this task. The random element is chosen by randrange() and then is accessed and removed from the list using pop()
Python3
# Python3 code to demonstrate working of# Remove random element from list# Using randrange() + pop()import random# initializing listtest_list = [6, 4, 8, 9, 10]# printing listprint("The original list : " + str(test_list))# Remove random element from list# Using randrange() + pop()test_list.pop(random.randrange(len(test_list)))# Printing resultprint("List after removal of random number : " + str(test_list)) |
The original list : [6, 4, 8, 9, 10] List after removal of random number : [6, 4, 8, 9]
Time Complexity: O(n), where n is the length of the list test_list
Auxiliary Space: O(n) additional space of size n is created where n is the number of elements in the res list
Another approach to remove a random element from a list in Python is using the random.choice() method. This method returns a random element from a given list. After getting the random element, it can be removed from the list using the list.remove() method.
Python3
import randomtest_list = [6, 4, 8, 9, 10]print("The original list : " + str(test_list))# remove a random element from listrandom_element = random.choice(test_list)test_list.remove(random_element)# Printing resultprint("List after removal of random number : " + str(test_list))#This code is contributed by Edula Vinay Kumar Reddy |
The original list : [6, 4, 8, 9, 10] List after removal of random number : [4, 8, 9, 10]
Time complexity: O(n)
Auxiliary Space: O(1)
Method : Using filter () and lambda():
Python3
# import the random libraryimport random# Initialize the listtest_list = [6, 4, 8, 9, 10]# Print the original listprint("The original list : " + str(test_list))# Use the random.choice() function to randomly select an element from the listrandom_element = random.choice(test_list)# Use the filter function and a lambda function to remove the selected element from the listtest_list = list(filter(lambda x: x != random_element, test_list))# Print the list after removal of the random elementprint("List after removal of random number : " + str(test_list))#This code is contributed by pinjala Jyothi |
The original list : [6, 4, 8, 9, 10] List after removal of random number : [4, 8, 9, 10]
Time complexity: O(n)
Auxiliary Space: O(n-1)
Method : Using del keyword
Python3
import randomtest_list = [6, 4, 8, 9, 10]random_element = random.choice(test_list)# Print the original listprint("The original list : " + str(test_list))del test_list[test_list.index(random_element)]print("List after removal of random number :", test_list)#This code is Contributed by Vinay Pinjala. |
The original list : [6, 4, 8, 9, 10] List after removal of random number : [6, 4, 8, 9]
Time complexity: O(n)
Auxiliary Space: O(1)
