Python – Check if List Contains all Elements of Another List

Python – Check if List Contains all Elements of Another List

To check if a list contains all elements of other list, use all() function with iterable generated from the list comprehension where each elements represent a boolean value if the element in the other list is present in the source list.

all() built-in Python function returns true if all the elements of this iterable are True.

As an alternate approach, we can also use nested for loop.

Examples

1: Check if List 1 Contains all Elements of List 2 using all()

In this example, we will take two lists: list_1 and list_2. We will initialize these lists with some elements. Then we shall write list comprehension and pass this as argument to all() method.

list_1 = ['a', 'b', 'c', 'd', 'e']
list_2 = ['a', 'c', 'e']

if all(x in list_1 for x in list_2) :
    print("List 1 contains all elements of list 2.")
else:
    print("List 1 does not contain all elements of list 2.")

Output

List 1 contains all elements of list 2.

2. Check if List 1 Contains all Elements of List 2 using Nested For

In this example, we will use nested for loop to check if a list (list_1) contains all elements of another list (list_2).

list_1 = ['a', 'b', 'c', 'd', 'e']
list_2 = ['a', 'c', 'e']

isPresent = True
for x in list_2:
    x_present = False
    for y in list_1:
        if x == y:
            x_present = True
            break
    if not x_present:
        isPresent = False
        break

if isPresent :
    print("List 1 contains all elements of list 2.")
else:
    print("List 1 does not contain all elements of list 2.")

Output

List 1 contains all elements of list 2.

Summary

In this tutorial of Python Examples, we learned how to check if a list contains all elements of another list.