using System;

using System.Linq;

public class Program

{

    public static void Main()

    {

        var input =

@"W 1, 2, 3

    W 4, 5, 6

        W 7, 8, 9";

        var output = string.Empty;

        var inputLines = input.Split('\n');

        foreach(var inputLine in inputLines) {

            // get leading whitespace for line... you can use Regex here to match

            // more WS characters if you'd like

            var leadingWsAmt = inputLine.Length - inputLine.TrimStart(' ').Length;

            var leadingWs = new string(' ', leadingWsAmt);

            string[] groups = inputLine.Split(',');

            string[] inputsOnLine = groups

                .Select(x => x.Trim())

                .Select((x, idx) => x + (idx < groups.Length - 1 ? "," : string.Empty) + "\n\t"+leadingWs)

                .ToArray();

            output += string.Join("", inputsOnLine);

        }

        output = output.Trim();

        Console.WriteLine(output);

    }

}