1\documentclass{article}
 2\usepackage[english]{babel}
 3
 4% Use packages
 5\usepackage{hhline}
 6\usepackage{booktabs}
 7\usepackage{amsmath}
 8\usepackage{amssymb}
 9\usepackage{amsthm}
10\usepackage{enumitem}
11\usepackage{graphicx}
12\usepackage{wrapfig}
13
14\graphicspath{ {../res} }
15
16\title{Error-correcting codes}
17\author{Marco Andronaco}
18
19\theoremstyle{definition}
20\newtheorem{definition}{Definition}
21
22\newtheorem{theorem}{Theorem}
23\newtheorem{proposition}{Proposition}
24
25\theoremstyle{definition}
26\newtheorem{example}{Example}
27
28\theoremstyle{definition}
29\newtheorem*{remark}{Remark}
30
31\makeatletter
32\renewcommand*\env@matrix[1][*\c@MaxMatrixCols c]{%
33  \hskip -\arraycolsep
34  \let\@ifnextchar\new@ifnextchar
35  \array{#1}}
36\makeatother
37
38\begin{document}