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I'm trying to put a frame around my code, but the frame has the wrong dimension. How can I set them right?
\begin{lstlisting}[language=C++,frame=single,tabsize=2,showspaces=false,showstringspaces=false,
keywordstyle=\color{blue},morekeywords={QStringList,QDate,QString,QIODevice},commentstyle=\...