Check if two arrays are equal or not Java

PROGRAM TO CHECK IF TWO ARRAYS ARE EQUAL OR NOT



Two arrays are said to be equal if both of them contain the same set of elements, arrangements (or permutation) 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. 


import java.util.*;
import java.io.*;
 
class Main {
    // Returns true if arr1[0..n-1] and arr2[0..m-1]
    // contain same elements.
    public static boolean areEqual(int arr1[], int arr2[])
    {
        int n = arr1.length;
        int m = arr2.length;
 
        // If lengths of arrays are not equal
        if (n != m)
            return false;
 
        // Store arr1[] elements and their counts in
        // hash map
        Map<Integer, Integer> map
            = new HashMap<Integer, Integer>();
        int count = 0;
        for (int i = 0; i < n; i++) {
            if (map.get(arr1[i]) == null)
                map.put(arr1[i], 1);
            else {
                count = map.get(arr1[i]);
                count++;
                map.put(arr1[i], count);
            }
        }
 
        // Traverse arr2[] elements and check if all
        // elements of arr2[] are present same number
        // of times or not.
        for (int i = 0; i < n; i++) {
            // If there is an element in arr2[], but
            // not in arr1[]
            if (!map.containsKey(arr2[i]))
                return false;
 
            // If an element of arr2[] appears more
            // times than it appears in arr1[]
            if (map.get(arr2[i]) == 0)
                return false;
 
            count = map.get(arr2[i]);
            --count;
            map.put(arr2[i], count);
        }
 
        return true;
    }
 
    // Driver code
    public static void main(String[] args)
    {
        int arr1[] = { 3, 5, 2, 5, 2 };
        int arr2[] = { 2, 3, 5, 5, 2 };
 
        if (areEqual(arr1, arr2))
            System.out.println("Yes");
        else
            System.out.println("No");
    }
}


OUTPUT
Yes

Comments

Post a Comment