What will be the output of the following C# code snippet?

class UnsafeCode
{
    unsafe static void Main()
    {
        string str = "this is a test";

            fixed (char* p = str)
           {
               for (int i = str.Length-1 ;p[i] != 0 ;i--)
               Console.Write(p[i]);
           }
       Console.ReadLine();
   }
}