Added comment code to tex file.

problemstatement.tex

 \documentclass[12pt]{article}
 
 \usepackage{xcolor} % for different colour comments
+
+%% Comments
+\newif\ifcomments\commentstrue
+
+\ifcomments
+\newcommand{\authornote}[3]{\textcolor{#1}{[#3 ---#2]}}
+\newcommand{\todo}[1]{\textcolor{red}{[TODO: #1]}}
+\else
+\newcommand{\authornote}[3]{}
+\newcommand{\todo}[1]{}
+\fi
+
+\newcommand{\wss}[1]{\authornote{magenta}{SS}{#1}}
+\newcommand{\hm}[1]{\authornote{blue}{HM}{#1}} %Hediyeh
+\newcommand{\tz}[1]{\authornote{blue}{TZ}{#1}} %Tahereh
+\newcommand{\pl}[1]{\authornote{blue}{PL}{#1}} %Peng
 \setlength{\parskip}{1em}
 
 \begin{document}