tex template

template.tex

\documentclass{article}
\usepackage{amsmath,amssymb,amsthm,amsfonts}
\usepackage{xcolor}

\newcommand{\public}[1]{\textcolor[rgb]{0.024,0.408,0.024}{#1}}
\newcommand{\private}[1]{\textcolor[rgb]{0.661,0.035,0.035}{#1}}

\newcommand{\FF}{\mathbb{F}}
\newcommand{\QQ}{\mathbb{Q}}
\newcommand{\ZZ}{\mathbb{Z}}

\theoremstyle{plain}
\newtheorem{thm}{Theorem}
\newtheorem{theorem}[thm]{Theorem}
\newtheorem{lemma}[thm]{Lemma}
\newtheorem{corollary}[thm]{Corollary}
\theoremstyle{remark}
\newtheorem{remark}[thm]{Remark}
\theoremstyle{definition}
\newtheorem{definition}[thm]{Definition}
\newtheorem{example}[thm]{Example}

\title{???}

\begin{document}

\maketitle

\begin{abstract}
  ???
\end{abstract}

\section{Introduction}

???

\bibliography{references}
\bibliographystyle{alpha}

\end{document}

For tikz:

\usepackage{tikz}

\[
\begin{tikzpicture}[node distance=1cm,auto]
    \draw (-2,0) ellipse (1);
    \node () at (-3.2,1.2)  {$V_1$};
    \node (j0) at (-2,-1)  {$\bullet$};
    \node[label={[shift={(0.5,-0.5)}]$j_1$}] (j1) at (-2,-2)  {$\bullet$};
    \draw[->] (j0) -> (j1);
\end{tikzpicture}
\]

For line numbers and todonotes:

\usepackage{lineno}
\linenumbers
\usepackage{todonotes}