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Python BasicsEasy
Array subset check
Learn how to solve the 'Array subset check' problem. This detailed resource details brute force and optimized approaches.
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?
Use simple arithmetic operators (like modulo `%`, division `//`), conditional checks, or loops to inspect number properties.
Edge Cases to Watch
- Empty list or null input variables
- Single item lists/arrays
- Extremely large input bounds causing integer or stack overflow
Ready to Solve?
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