Check Equal Arrays

Problem Description

Given two arrays arr1 and arr2 of equal size, the task is to find whether the given arrays are equal. Two arrays are said to be equal if both contain the same set of elements, arrangements (or permutations) of elements may be different though. Note: If there are repetitions, then counts of repeated elements must also be the same for two arrays to be equal.

Examples

Example 1:

Input: arr1[] = [1, 2, 5, 4, 0], arr2[] = [2, 4, 5, 0, 1]
Output: true
Explanation: Both the array can be rearranged to [0,1,2,4,5]

Example 2:

Input: arr1[] = [1, 2, 5], arr2[] = [2, 4, 15]
Output: false
Explanation: arr1[] and arr2[] have only one common value.

Expected Time Complexity: O(n)

Expected Auxiliary Space: O(n)

Constraints

• 1<= arr1.size, arr2.size<=10^7

Problem Explanation

The task is to traverse the array and search the number.

Code Implementation

C++ Solution

#include <algorithm>
#include <vector>

bool areEqual(std::vector<int> arr1, std::vector<int> arr2) {
    std::sort(arr1.begin(), arr1.end());
    std::sort(arr2.begin(), arr2.end());
    return arr1 == arr2;
}

import java.util.Arrays;

public class Main {
    public static boolean areEqual(int[] arr1, int[] arr2) {
        Arrays.sort(arr1);
        Arrays.sort(arr2);
        return Arrays.equals(arr1, arr2);
    }
}

def are_equal(arr1, arr2):
    return sorted(arr1) == sorted(arr2)

function areEqual(arr1, arr2) {
    return arr1.sort((a, b) => a - b).every((value, index) => value === arr2.sort((a, b) => a - b)[index]);
}

Solution Logic:

In the solution, the arrays are sorted and then compared. If the sorted arrays are equal, then the original arrays contain the same set of elements, regardless of order. Note that this approach assumes that the arrays contain only elements that can be compared using the default comparison operators (e.g., numbers, strings). If the arrays contain custom objects, a custom comparison function may be needed.

Time Complexity

• The time complexity is $O(log(n))$ where n is the input number.

Space Complexity

• The auxiliary space complexity is $O(1)$ due to the only extra memory used is for temporary variables while swapping two values in Array.