%@metapost:3Scratchexo11.mp Quel est le but des trois algorithmes ci-dessous ? \begin{center} \includegraphics[width=0.45\linewidth]{3Scratchexo11.1}\kern0.05\linewidth \includegraphics[width=0.45\linewidth]{3Scratchexo11.2} \end{center} \begin{center} \includegraphics[width=0.45\linewidth]{3Scratchexo11.3} \end{center}