[Tex/LaTex] Overlapping numbers and titles in toc

formattingtable of contents

How can i change formatting of the table of contents to avoid section numbering and section title to overlap?

Document:

\documentclass[10pt,oneside,notitlepage]{book}

% Use Heuristica Font
\usepackage{heuristica}
\usepackage[heuristica,vvarbb,bigdelims]{newtxmath}
\renewcommand*\oldstylenums[1]{\textosf{#1}}


\begin{document}

\tableofcontents

\part{Part one}

\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}


\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}

\end{document}

Example output:
Output example

Best Answer

The space needed by the section number(s) is too small. Using tocloft this spacing can be controlled by the length register \cftsecnumwidth, adding some value with \addtolength{\cftsecnumwidth}{10pt} will improve the spacing.

The value of 10pt can be changed of course.

\documentclass[10pt,oneside,notitlepage]{book}

% Use Heuristica Font
\usepackage{heuristica}
\usepackage[heuristica,vvarbb,bigdelims]{newtxmath}
\renewcommand*\oldstylenums[1]{\textosf{#1}}
\usepackage{tocloft}

\addtolength{\cftsecnumwidth}{10pt}

\begin{document}

\tableofcontents

\part{Part one}

\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}
\chapter{Chapter Oh}


\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}
\section{Chapter Hi}

\end{document}

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