\myheading{Division by zero}

If division by zero is unwrapped by sanitizing check, and exception isn't caught, it can crash process.

Let's calculate simple expression $\frac{x}{2y + 4z - 12}$.
We can add a warning into \TT{\_\_div\_\_} method:

\lstinputlisting[style=custompy]{\CURPATH/7_div/1.py}

\dots so it will report about dangerous states and conditions:

\begin{lstlisting}
warning: division by zero if (((y*2)+(z*4))-12)==0
(x/(((y*2)+(z*4))-12))
\end{lstlisting}

This equation is easy to solve, let's try Wolfram Mathematica this time:

\begin{lstlisting}
In[]:= FindInstance[{(y*2 + z*4) - 12 == 0}, {y, z}, Integers]
Out[]= {{y -> 0, z -> 3}}
\end{lstlisting}

These values for $y$ and $z$ can also be called ``inputs of death''.