import java.util.*;

public class Lotto642 {
    public static void main(String[] args) {
        final int numCount = 6;
        final int maxNum = 42;
        System.out.printf("%d/%d LOTTO%n", numCount, maxNum);
        System.out.printf("Enter %d numbers between 1 and %d (no duplicates):%n",numCount,maxNum);
        final Set<Integer> userNums = getUserNumbers(numCount, maxNum);
        final Set<Integer> winningNums = getRandomSet(numCount, maxNum);
        final Set<Integer> intersection = new HashSet<>(winningNums);
        intersection.retainAll(userNums);

        System.out.println("\nYour numbers: " + winningNums);
        System.out.println("Winning numbers: " + userNums);
        System.out.println("You matched " + intersection.size() + " number(s).");

        switch (intersection.size()) {
            case 6 -> System.out.println("JACKPOT!");
            case 3, 4, 5 -> System.out.println("MINOR prize!");
            default -> System.out.println("Sorry, no prize. Better luck next time!");
        }
    }
    private static Set<Integer> getUserNumbers(int numCount, int maxNum) {
        final Scanner s = new Scanner(System.in);
        final Set<Integer> nums = new HashSet<>(numCount);
        while (nums.size() < numCount) {
            System.out.printf("Enter number %d: ", nums.size() + 1);
            final int num = s.nextInt();
            if(nums.contains(num)) {
                System.out.println("Duplicate number! Try again.");
                continue;
            }
            if (num > maxNum || num < 1) {
                System.out.println("Invalid! Number must be between 1 and " + maxNum);
                continue;
            }
            nums.add(num);
        }
        return nums;
    }

    private static Set<Integer> getRandomSet(int numCount, int maxNum) {
        Set<Integer> nums = new HashSet<>();
        Random random = new Random();
        while (nums.size() < numCount) {
            nums.add(random.nextInt(maxNum) + 1);
            // Sets ignore duplicates, so the size will only increase with distinct numbers
        }
        return nums;
    }
}