Problem:
Sum of Numbers

Write a program which reads an integer and prints sum of its digits.

Input

The input consists of multiple datasets. For each dataset, an integer x is given in a line. The number of digits in x does not exceed 1000.

The input ends with a line including single zero. Your program should not process for this terminal symbol.

Output

For each dataset, print the sum of digits in x.

Sample Input

123
55
1000
0

Sample Output

6
10
1

Solution in C# (judge verdict: Runtime Error)

using System;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Text.RegularExpressions;
using System.Text;

namespace Fish.aizu
{
	public static class AizuOnlineJudge
	{
		public static int[] SplitToInts(string line)
		{
			return line.Split(' ').Select(x => int.Parse(x)).ToArray();
		}
		public static double[] SplitToDoubles(string line)
		{
			return line.Split(' ').Select(x => double.Parse(x)).ToArray();
		}
		public static long[] SplitToLongs(string line)
		{
			return line.Split(' ').Select(x => long.Parse(x)).ToArray();
		}
		public static int Main()
		{
			Compute(Console.In, Console.Out);
			return 0;
		}
		
		public static void Compute(TextReader reader, TextWriter writer)
		{
			string line = null;
			while (null != (line = reader.ReadLine()))
			{
				var n = int.Parse(line);
				if (0 == n) 
				{
					return;
				}
				int sum = 0;
				while (n > 0)
				{
					sum += n % 10;
					n /= 10;
				}
				writer.WriteLine(sum);
			}
		}
	}
}