deletions | additions       diff --git a/header.tex b/header.tex  index 7e61fc3..26c729b 100644  --- a/header.tex  +++ b/header.tex 
...
\newcommand{\TRUE}{\textrm{TRUE}}  \newcommand{\NN}{\mathbb{N}}  \newtheorem{Theorem}{Theorem} \newtheorem{Definition}{Definition}  \newtheorem{Exercise}{Exercise}