Python BasicsEasy

Array subset check

Detailed guide and Python implementation for the 'Array subset check' problem.

Problem Statement

Easy

Write a function is_subset(arr1, arr2) that checks if arr1 is a subset of arr2. Return True if every element of arr1 exists in arr2 (considering duplicates), False otherwise.

Constraints
  • 0 <= len(arr1) <= len(arr2) <= 10^5
  • -10^6 <= elements <= 10^6

Examples

Example 1
Input
arr1 = [1, 2, 3], arr2 = [1, 2, 3, 4, 5]
Output
True
Explanation

All elements of arr1 (1, 2, 3) exist in arr2.

Example 2
Input
arr1 = [1, 2, 6], arr2 = [1, 2, 3, 4, 5]
Output
False
Explanation

6 is in arr1 but not in arr2.

Example 3
Input
arr1 = [], arr2 = [1, 2, 3]
Output
True
Explanation

An empty set is a subset of any set.

Need a Hint?
Consider using Arrays-specific data structures like sets or heaps.
Edge Cases to Watch
  • Empty input structures
  • Single element inputs
  • Large numerical bounds

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