Onnenluku

import java.util.HashSet;
import java.util.Scanner;

public class K19_2_5_Onnenluku {
	static String[] numbers = new String[72];
	static HashSet<String> answers = new HashSet<>();

	public static void main(String[] args) {
		int x = 0;
		for (int i = 12; i < 99; i++) {
			if (i % 10 != 0 && (i / 10 != i % 10)) {
				numbers[x] = i + "";
				x++;
			}
		}
//		Scanner s = new Scanner(System.in);
//		String input = s.nextLine();
//		s.close();
//		String[] split = input.split("\\s+");

//		solve(split[0], split[1]);
		solve("0", "10000");
		System.out.println(answers.size());
	}

	private static void solve(String min, String max) {
		for (int i = 0; i < numbers.length; i++) {
			String s = numbers[i];
			recursion(s, min, max, s.charAt(0), s.charAt(1));
		}
	}

	private static void recursion(String s, String min, String max, char a, char b) {
		if (Integer.parseInt(s) > Integer.parseInt(max))
			return;
		if (Integer.parseInt(s) >= Integer.parseInt(min)) {
			answers.add(s);
			System.out.println(s);
		}
		if (s.length() == max.length()) {
			return;
		}
		recursion(s += a, min,  max, a, b);
		s = s.substring(0, s.length() - 1);
		recursion(s = a + s, min, max, a, b);
		s = s.substring(1, s.length());
		recursion(s += b, min, max, a, b);
	}
}

Test 1

Group: 1

Verdict: WRONG ANSWER

Test 2

Group: 1

Verdict: WRONG ANSWER

Test 3

Group: 1

Verdict: WRONG ANSWER

Test 4

Group: 1

Verdict: WRONG ANSWER

Test 5

Group: 1

Verdict: WRONG ANSWER

Test 6

Group: 2

Verdict: WRONG ANSWER

Test 7

Group: 2

Verdict: WRONG ANSWER

Test 8

Group: 2

Verdict: WRONG ANSWER

Test 9

Group: 2

Verdict: WRONG ANSWER

Test 10

Group: 2

Verdict: WRONG ANSWER

Test 11

Group: 3

Verdict: WRONG ANSWER

Test 12

Group: 3

Verdict: WRONG ANSWER

Test 13

Group: 3

Verdict: WRONG ANSWER

Test 14

Group: 3

Verdict: WRONG ANSWER

Test 15

Group: 3

Verdict: WRONG ANSWER