ArrayIntersection.java

import java.util.HashMap;

public class ArrayIntersection {

    public static void printIntersection(int arr1[], int arr2[]) {
        HashMap<Integer, Integer> map = new HashMap<>();
        for (int i = 0; i < arr1.length; i++) {
            if (map.containsKey(arr1[i])) {
                map.put(arr1[i], map.get(arr1[i]) + 1);
            } else {
                map.put(arr1[i], 1);
            }
        }

        for (int i = 0; i < arr2.length; i++) {
            if (map.containsKey(arr2[i])) {
                if (map.get(arr2[i]) > 0) {
                    System.out.print(arr2[i] + " ");
                    map.put(arr2[i], map.get(arr2[i]) - 1);
                }
            }
        }
    }

    public static void main(String[] args) {
        int arr1[] = { 1, 4, 5, 2, 2, 3, 6, 5, 3, 2 };
        int arr2[] = { 2, 3, 2, 6, 6, 5, 1 };

        printIntersection(arr1, arr2);
    }
}