30 tikz的图node 里面怎么用 latex3 循环功能?

\documentclass{article}
\usepackage{ctex}
\usepackage{tikz}
\ExplSyntaxOn
\int_new:N \l_exercise_number_int
\NewDocumentCommand{\datika}{ m }{
  \int_set:Nn \l_exercise_number_int { #1 }
  \begin{tikzpicture}[overlay,remember~picture]
    \node[
        fill=gray!10,
        rounded~corners,
        shift={(1,0)},
        align=left,
        font={\baselineskip=2.6em}
    ] at (current~page.west){
        {\heiti 答题卡} \\
        \int_step_inline:nn
          { \l_exercise_number_int }
          { ##1.\underline{\hspace{1cm}} \\ }
    };
  \end{tikzpicture}
}
\ExplSyntaxOff
\begin{document}

hello\datika{15}

\end{document}

或者

\documentclass{article}
\usepackage{ctex}
\usepackage{tikz}
\ExplSyntaxOn
\int_new:N \l_exercise_number_int
\int_set:Nn \g_tmpa_int { 1 }
\NewDocumentCommand{\datika}{ m }{
  \int_set:Nn \l_exercise_number_int { #1 }
  \begin{tikzpicture}[overlay,remember~picture]
    \node[
        fill=gray!10,
        rounded~corners,
        shift={(1,0)},
        align=left,
        font={\baselineskip=2.6em}
    ] at (current~page.west){
        {\heiti 答题卡} \\
        \int_step_inline:nn
          { \l_exercise_number_int - 1 }
          { \int_use:N \g_tmpa_int.\underline{\hspace{1cm}} \int_gincr:N \g_tmpa_int \\ }
        \int_use:N \l_exercise_number_int. \underline{\hspace{1cm}}
    };
  \end{tikzpicture}
}
\ExplSyntaxOff
\begin{document}

hello\datika{15}

\end{document}