Warning(s):

(16:17) The variable 'test' is assigned but its value is never used

Error(s):

Exception in user code:

System.FormatException: Input string was not in a correct format.
   at System.Text.StringBuilder.AppendFormat(IFormatProvider provider, String format, Object[] args)
   at System.String.Format(IFormatProvider provider, String format, Object[] args)
   at System.String.Format(String format, Object arg0)
   at Rextester.Program.Main(String[] args)