如何删除左上角第一个单元格的线条？

Question

请问如何删除左上角第一个空单元格的行？

\documentclass[french]{beamer}
\usepackage{babel}
\usepackage{adjustbox}
\usepackage{array}
\newcolumntype{C}[1]{>{\centering\arraybackslash}p{#1}}
\begin{document}   

\begingroup
\defbeamertemplate{enumerate item}{image}{\small\includegraphics[height=1.8ex]{images/gofor}}
\makeatletter
\def\@listii{\leftmargin\leftmarginii
              \topsep    2ex
              \parsep    0\p@   \@plus\p@
              \itemsep   \parsep}
\makeatother
\begin{frame}{Conclusion}
\begin{table}
\centering
\caption{Comparatif entre ATL et MFC}
\vspace{0.4cm}
\begin{tabular}{
  | C{0.07\textwidth}
  *{3}{|C{\dimexpr0.22\textwidth-2\tabcolsep\relax}}
  ||C{\dimexpr0.22\textwidth-2\tabcolsep\relax} |
  }
\hline
& {\fontsize{9}{9}\selectfont Gestion avancée des threads} & {\fontsize{9}{9}\selectfont Gestion de la mémoire} & {\fontsize{9}{9}\selectfont Vitesse d'exécution} & {\fontsize{9}{9}\selectfont Difficulté} \\
\hline
MFC & \adjustbox{valign=c}{\includegraphics[height=1.8ex]{example-image-a}} & \adjustbox{valign=c}{\includegraphics[height=1.8ex]{example-image-a}} & \adjustbox{valign=c}{\includegraphics[height=1.8ex]{example-image-a}} & \textcolor{green}{F}\\
\hline
ATL & \adjustbox{valign=c}{\includegraphics[height=1.8ex]{example-image-a}} &\adjustbox{valign=c}{\includegraphics[height=1.8ex]{example-image-a}\includegraphics[height=1.8ex]{example-image-a}} & \adjustbox{valign=c}{\includegraphics[height=1.8ex]{example-image-a}\includegraphics[height=1.8ex]{example-image-a}\includegraphics[height=1.8ex]{example-image-a}} & \textcolor{red}{D} \\
\hline
\end{tabular}
\end{table}
\end{frame}
\endgroup
\end{document}

多谢！

Answer 1

使用\cline和\multicolumn：

\documentclass[french]{beamer}
\usepackage{babel}
\usepackage{adjustbox}
\usepackage{array}
\newcolumntype{C}[1]{>{\centering\arraybackslash}p{#1}}
\begin{document}   

\begingroup
\defbeamertemplate{enumerate item}{image}{\small\includegraphics[height=1.8ex]{images/gofor}}
\makeatletter
\def\@listii{\leftmargin\leftmarginii
              \topsep    2ex
              \parsep    0\p@   \@plus\p@
              \itemsep   \parsep}
\makeatother
\begin{frame}{Conclusion}
\begin{table}
\centering
\caption{Comparatif entre ATL et MFC}
\vspace{0.4cm}
\begin{tabular}{
  | C{0.07\textwidth}
  *{3}{|C{\dimexpr0.22\textwidth-2\tabcolsep\relax}}
  ||C{\dimexpr0.22\textwidth-2\tabcolsep\relax} |
  }
\cline{2-5}
\multicolumn{1}{c|}{} & {\fontsize{9}{9}\selectfont Gestion avancée des threads} & {\fontsize{9}{9}\selectfont Gestion de la mémoire} & {\fontsize{9}{9}\selectfont Vitesse d'exécution} & {\fontsize{9}{9}\selectfont Difficulté} \\
\hline
MFC & \adjustbox{valign=c}{\includegraphics[height=1.8ex]{example-image-a}} & \adjustbox{valign=c}{\includegraphics[height=1.8ex]{example-image-a}} & \adjustbox{valign=c}{\includegraphics[height=1.8ex]{example-image-a}} & \textcolor{green}{F}\\
\hline
ATL & \adjustbox{valign=c}{\includegraphics[height=1.8ex]{example-image-a}} &\adjustbox{valign=c}{\includegraphics[height=1.8ex]{example-image-a}\includegraphics[height=1.8ex]{example-image-a}} & \adjustbox{valign=c}{\includegraphics[height=1.8ex]{example-image-a}\includegraphics[height=1.8ex]{example-image-a}\includegraphics[height=1.8ex]{example-image-a}} & \textcolor{red}{D} \\
\hline
\end{tabular}
\end{table}
\end{frame}
\endgroup
\end{document}