Nested enumerate starting from 0

Here is my latex code:

\begin{enumerate}
\item
\begin{enumerate}
\item  I do not feel sad.
\item I am sad all the time and I can't snap out of it.
\item I am so sad and unhappy that I can't stand it.
\end{enumerate}
\end{enumerate}


and here is the output

and here is what I want

As you see from the second picture, the number starts with 0 and it starts from the second row. How can I obtain this?

You can do it like this:

\documentclass{article}

\begin{document}
\begin{enumerate}
\item

\begin{enumerate}\setcounter{enumii}{-1}\renewcommand\theenumii{\arabic{enumii}}
\item  I do not feel sad.
\item I am sad all the time and I can't snap out of it.
\item I am so sad and unhappy that I can't stand it.
\end{enumerate}
\end{enumerate}
\end{document}


You also can define as \settozero the above command like:

\def\settozero{\setcounter{enumii}{-1}\renewcommand\theenumii{\arabic{enumii}}}


and then you can use it just when the inner enumeration starts:

\documentclass{article}

\def\settozero{\setcounter{enumii}{-1}\renewcommand\theenumii{\arabic{enumii}}}

\begin{document}
\begin{enumerate}
\item

\begin{enumerate}\settozero
\item  I do not feel sad.
\item I am sad all the time and I can't snap out of it.
\item I am so sad and unhappy that I can't stand it.
\end{enumerate}
\end{enumerate}
\end{document}


And somehow more automated:

\documentclass{article}

\def\settozero{\setcounter{enumii}{-1}\renewcommand\theenumii{\arabic{enumii}}}

\newenvironment{myenumerate}{\begin{enumerate}\ifx\c@enumii\undefined\relax\else\settozero\fi}{\end{enumerate}}
\begin{document}
\begin{enumerate}
\item

\begin{myenumerate}
\item  I do not feel sad.
\item I am sad all the time and I can't snap out of it.
\item I am so sad and unhappy that I can't stand it.
\end{myenumerate}

\item
\begin{myenumerate}
\item Test 0
\item Test 1
\end{myenumerate}

\end{enumerate}
\end{document}


Output:

• They perfectly works on a new document, but I copied the code above and pasted to my document and it does not work the same way. The first raw has no number and others have a, b and c. Any idea why? – Günal Oct 19 '17 at 14:10
• Try the last one and if it doesn't works just give me more information about your document. You may be redefine nested enumerations and have only "enumi" and "\c@enumi" without "enumii" ot "c@enumii"... – koleygr Oct 19 '17 at 14:11
• I see... I found what is your problem.... You use enumitem package... @StevenB.Segletes soplution is fine for your case. If you want you can just extend my automation if possible – koleygr Oct 19 '17 at 14:23
• Did you removed enumitem package? – koleygr Oct 19 '17 at 14:25
• Ok... If you/or someone else need enumitem the solution from @StevenB is the option for your/his case. – koleygr Oct 19 '17 at 14:56
\documentclass{article}
\usepackage{enumitem}
\begin{document}
\begin{enumerate}
\item
\begin{enumerate}[label=\arabic*,itemindent=.5in,labelsep=.5in,start=0]
\item[]
\item  I do not feel sad.

• enumitem provides the start option, so start=0 is simpler. – Andrew Swann Oct 19 '17 at 14:26