UVA 11332 Java

import java.util.*;
 
public class main{
  public static void main(String[] args) {
    Scanner sc=new Scanner(System.in);
	while(sc.hasNextLine())
	{
		String str = sc.nextLine();
		if(str.equals("0"))
			break;
		while(str.length() > 1)
		{
			int num = 0;
			for(int i = 0; i < str.length(); i++)
				num += str.charAt(i) - '0';
			str = Integer.toString(num);
		}
		System.out.println(str);
	}
  }
};

import java.util.*;
 
public class main{
  public static void main(String[] args) {
    Scanner sc=new Scanner(System.in);
	while(sc.hasNextLine())
	{
		int num = Integer.parseInt(sc.nextLine());
		if(num == 0)
			break;
		while(num >= 10)
		{
			int temp = 0;
			while(num != 0)
			{
				temp += num % 10;
				num /= 10;
			}
			num = temp;
		}
		System.out.println(num);
	}
  }
};