MaxDigitInNumber

import java.util.Scanner;

public class test {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int number = Integer.parseInt(scanner.nextLine());
        int maxNumber = Integer.MIN_VALUE;

        do {
            int num = number % 10;

            if (num > maxNumber) {
                maxNumber = num;
            }
            number /= 10;
        }
        while (number != 0);

        System.out.println("Max number is: " + maxNumber);
    }
}