//brue-force
//check if a2 is a subset of a1 when a2 has no duplicates.
//check if a2 is a subset of a1 when a2 has duplicates.
import java.util.*;
class Ideone {
    public static void main(String[] args) throws java.lang.Exception {
        int[] a1 = {1, 2, 3, 3, 3, 3, 4, 1, 5, 2, 7, 6};
        int[] a2 = {1, 6, 3, 2, 2};  // has duplicates
 
        int[] visited = new int[a1.length]; 
 
        boolean isSubset = true;
 
        for (int i = 0; i < a2.length; i++) {
            boolean found = false;
            for (int j = 0; j < a1.length; j++) {
                if (a2[i] == a1[j] && visited[j] == 0) {
                    found = true;
                    visited[j] = 1; 
                    break;
                }
            }
            if (!found) {
                isSubset = false;
                break;
            }
        }
 
        if (isSubset) {
            System.out.println("is a subset");
        } else {
            System.out.println("is not a subset");
        }
    }
}
 

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