Checking List Containment in Python

Introduction

In Python, it is often necessary to check if one list is contained in another list. This can be a bit tricky, especially if the order of the elements in the lists doesn't matter. In this challenge, you will write a function that checks if the elements of one list are contained in another list, regardless of order.

Skills Graph

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List Containment

Write a function is_contained_in(a, b) that takes two lists as arguments and returns True if all the elements of list a are contained in list b, regardless of order. Otherwise, the function should return False.

To solve this problem, you can use the following approach:

Loop through each unique value in list a.
For each value, check if it appears more times in list a than in list b.
If any value appears more times in list a than in list b, return False.
If all values in list a appear in list b at least as many times as they appear in list a, return True.

def is_contained_in(a, b):
  for v in set(a):
    if a.count(v) > b.count(v):
      return False
  return True

is_contained_in([1, 4], [2, 4, 1]) ## True

Summary

In this challenge, you have learned how to check if one list is contained in another list, regardless of order. You have written a function that takes two lists as arguments and returns True if all the elements of list a are contained in list b, regardless of order.

Checking List Containment in Python

Introduction

Skills Graph

List Containment

Summary

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