insert images with no vertical distance in (la-)tex

I'm trying this, but I get a little distance.

\documentclass{article}
\usepackage{graphicx}
\usepackage[a3paper,landscape]{geometry}
\begin{document}

\includegraphics[width=5cm, height=5cm]{1.png}\includegraphics[width=5cm, height=5cm]{1.png}\includegraphics[width=5cm, height=5cm]{1.png}\includegraphics[width=5cm, height=5cm]{1.png}

 \includegraphics[width=5cm, height=5cm]{1.png}\includegraphics[width=5cm, height=5cm]{1.png}\includegraphics[width=5cm, height=5cm]{1.png}\includegraphics[width=5cm, height=5cm]{1.png}

\includegraphics[width=5cm, height=5cm]{1.png}\includegraphics[width=5cm, height=5cm]{1.png}\includegraphics[width=5cm, height=5cm]{1.png}\includegrap开发者_JAVA百科hics[width=5cm, height=5cm]{1.png}

\includegraphics[width=5cm, height=5cm]{1.png}\includegraphics[width=5cm, height=5cm]{1.png}\includegraphics[width=5cm, height=5cm]{1.png}\includegraphics[width=5cm, height=5cm]{1.png}


\end{document}

Change it like this:

\includegraphics[width=5cm, height=5cm]{1.png}\hspace*{-1pt}\includegraphics[width=5cm, height=5cm]{1.png}\hspace*{-1pt}\includegraphics[width=5cm, height=5cm]{1.png}