main.tex

% pdflatex
\documentclass[twoside,a5paper,12pt]{extbook}
\usepackage[T2A]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[english,russian]{babel} 
\usepackage[twoside, includehead, margin=10mm, left=25mm, bottom=15mm, headsep=2mm]{geometry}
\usepackage{indentfirst}
\usepackage{lastpage}
\usepackage{graphicx}
\usepackage{wrapfig}
\usepackage{tabularx}
\usepackage{subfiles}
%\usepackage{amsmath}
%\usepackage{multicol}

\usepackage{enumitem}
\setlist{nosep}

\usepackage{fancyhdr}
\pagestyle{fancy}
\fancyhf{}
\fancyhead[LE,RO]{\thepage}
\fancyhead[RE,LO]{\fontsize{10}{12}\rightmark}

\usepackage{titlesec}
\titleformat{\chapter}[display]{\normalfont\huge\bfseries}{}{20pt}{\Huge}
\titlespacing*{\chapter}{0pt}{-36pt}{24pt}   % 50 40
\titlespacing*{\section}{0pt}{12pt}{12pt}    % l t b
\titlespacing*{\subsection}{0pt}{6pt}{6pt}

% Эпиграфы всегда верстают на суженный формат (от ⅓ до ⅔ формата строки основного набора) 
\usepackage{epigraph}
\setlength{\epigraphwidth}{0.5\textwidth}

\usepackage{listings}
\lstset{
    basicstyle=\small,
    numbers=left,
    language=C,
    frame=single,
    showstringspaces=false,
    breaklines=true,
    breakatwhitespace=false,
    stringstyle=\ttfamily,
    mathescape=true,
    commentstyle=\color{red},
}

\usepackage{hyperref}
\hypersetup{
    colorlinks=true,
    linkcolor=blue,
    filecolor=magenta,      
    urlcolor=cyan,
    bookmarks=true,
    pdftitle={Методические указания к/р ИВТ заочка},
    pdfauthor={Ермаков А.В.},
}

\RequirePackage{caption}
\DeclareCaptionLabelSeparator{defffis}{ --- }
\captionsetup{justification=centering,labelsep=defffis}

% https://tex.stackexchange.com/questions/23921/how-to-shorten-shrink-spaces-between-words
\fontdimen3\font=4pt
\hfuzz=4pt


\begin{document}
\subfile{title}
\subfile{page2}
\tableofcontents
\subfile{00-intro}
\subfile{01}
\subfile{02}
\subfile{03}
\subfile{ref}
\end{document}