6. Random Hands of 5 Cards

import java.util.Random;
import java.util.Scanner;


public class _06_RandomHandsOf5Cards {

    public static void main(String[] args) {
        Scanner sc = new Scanner (System.in);
        System.out.println("Enter the count of hands");
        int hands = sc.nextInt();
        String[]  cards = {"2", "3", "4", "5", "6", "7", "8", "9", "10", "J", "Q", "K", "A"};
        char[] patterns = {'♣', '♦', '♥', '♠'};
        boolean[] isCardUsed = new boolean[52];

        for (int i = 0; i < hands; i++) {
            for (int j = 0; j < 5; j++) {
                Random r = new Random();
                int card;
                int pattern;
                do {
                    card = r.nextInt(12);
                    pattern = r.nextInt(4);
                    if (! isCardUsed[card * 4 + pattern]) {
                        System.out.print(cards[card] + "" + patterns[pattern] + " ");
                        isCardUsed[card * 4 + pattern] = true;
                        break;
                    }
                }
                while(isCardUsed[card * 4 + pattern]);
            }
            System.out.println();
        }

    }

}