deletions | additions       diff --git a/Ex 1.tex b/Ex 1.tex  index 3521c87..aad76dc 100644  --- a/Ex 1.tex  +++ b/Ex 1.tex 
...
\newcommand{\empty}{\varnothing}  \newcommand{\wp}[2]{wp(#1, #2)}  \newcommand{\if}[2]{if(#1) \{ #2 \}}  \newcommand{\else}[2]{else(#1) \newcommand{\else}[1]{else  \{ #2 #1  \}} \newcommand{\ie}[3]{\if{#1}{#2} \else{#3}}  Given:  \begin{equation} 
...
\begin{equation}  \begin{split}  \wp{if(x \wp{\ie{x  < 0) \{ y 0}{y  := -x \} else \{ -x}{  y := x }, R ) }}{R}  & \iff \\ (x < 0 \to wp( y:= -x, R )) \land (0 \leq x \to wp( y:= x, R )  \end{split}  \end{equation}