using System;
using System.Globalization;
using System.Linq;
using System.Collections.Generic;

public class Test
{
	public static void Main()
	{
        string text = "hello \\\"World\\\"";
        var  builder = new System.Text.StringBuilder();
        builder.Append(text[0] == '"' ? "\\\"" : text.Substring(0, 1));
        for (int i = 1; i < text.Length; i++)
        {
            Char next = text[i];
            Char last = text[i - 1];
            if (next == '"' && last != '\\')
            {
                builder.Append("\\\"");
            }
            else
               builder.Append(next);
        }
        Console.WriteLine(builder.ToString());
	}
}