import java.util.Scanner;

public class lab22 {

    public static int inputNumber() {
        Scanner scanner = new Scanner(System.in);
        final int MAX_NUMBER = 100000000;
        boolean isIncorrect;
        int number;
        number = 0;
        System.out.printf("Введите натуральное число не большее, чем %,d \n", MAX_NUMBER);
        do {
            isIncorrect = false;
            try {
                number = Integer.parseInt(scanner.nextLine());
            } catch (Exception ex) {
                System.out.printf("Нужно ввести натуральное число, не большее, чем %,d \n", MAX_NUMBER);
                isIncorrect = true;
            }
            if (!isIncorrect && (number < 1 || number > MAX_NUMBER)) {
                System.out.printf("Число должно быть больше 0 и не больше чем %,d \n", MAX_NUMBER);
                isIncorrect = true;
            }
        } while (isIncorrect);
        scanner.close();
        return number;
    }


    public static int searchMaxCountOfRepeats(int number) {
        int maxCountOfRepeats, counter, previous, singleNumber, newNumber;
        maxCountOfRepeats = 0;
        while (number > 0) {
            counter = 1;
            singleNumber = number % 10;
            previous = singleNumber;
            number = number / 10;
            newNumber = number;
            while (newNumber > 0)
            {
                singleNumber = newNumber % 10;
                newNumber = newNumber / 10;
                if (previous == singleNumber)
                    counter++;
                if (counter > maxCountOfRepeats)
                    maxCountOfRepeats = counter;
            }
        }
        return maxCountOfRepeats;
    }

    public static void allSolutions(int number, int maxCountOfRepeats) {
        int counter, previous, singleNumber, newNumber;
        while (number > 0) {
            counter = 1;
            singleNumber = number % 10;
            previous = singleNumber;
            number = number / 10;
            newNumber = number;
            while (newNumber > 0) {
                singleNumber = newNumber % 10;
                newNumber = newNumber / 10;
                if (previous == singleNumber) {
                    counter++;
                    if (counter == maxCountOfRepeats)
                        System.out.print(previous + " ");
                }
            }
        }
    }

    public static void printResult(int number, int maxCountOfRepeats) {
        System.out.println("Самая часто встречающаяся цифра/цифры: ");
        if (maxCountOfRepeats == 1)
            System.out.println("Такой цифры нет.");
        if (maxCountOfRepeats == 0)
            System.out.println(number);
        else
            allSolutions(number, maxCountOfRepeats);
    }


    public static void main(String[] args) {
        int maxCountOfRepeats, number;
        System.out.println("Программа позволяет узнать, какая цифра в данном числе встречается чаще всего.");
        number = inputNumber();
        maxCountOfRepeats = searchMaxCountOfRepeats(number);
        printResult(number, maxCountOfRepeats);
    }
}