Value range about [closes #5]

chapter01.tex

@@ -286,7 +286,7 @@ Still, it is good to know that
 the \texttt{g++} compiler also provides
 an 128-bit type \texttt{\_\_int128\_t}
 with value range
-$-2^{127} \ldots 2^{127}-1$ or $-10^{38} \ldots 10^{38}$.
+$-2^{127} \ldots 2^{127}-1$ or about $-10^{38} \ldots 10^{38}$.
 However, this type is not available in all contest systems.
 
 \subsubsection{Modular arithmetic}