If you draw two circles that are exactly the same in all aspects (location, size, etc...) except they have different colors, then the "border" of the underlying circle is showing through.
\documentclass[10pt]{book}
\usepackage{xcolor}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
...
% LaTeX3-Version
\documentclass{article}
\usepackage{expl3}
\parindent 0 pt
\parskip 1.5 ex
\ExplSyntaxOn
\int_new:N \l_beers_count_int
\int_set:Nn \l_beers_count_int {98}
\cs_new:Npn \beers
{
\prg_replicate:nn { 99 } { \beers_print: \int_decr:N \l_beers_count_int }
}
\cs_new:Npn \beers_print:
{
\beer_number:nn { ~ on ~ the ~ wall }{ 1 }, ~
\beer_number:nn { } { 1 }, \\
Take ~ one ~ down ~ and ~ pass ~ it ~ around, \\
\beer_number:nn { ~ on ~ the ~ wall } { 0 }.\par
}
\cs_new:Npn \beer_number:nn #1 #2
2
Instead of 98 one can initialize the counter to 99 and use {0} in the first two calls of \beer_number:nn and {-1} in the third call, which is better. :)
If you draw two circles that are exactly the same in all aspects (location, size, etc...) except they have different colors, then the "border" of the underlying circle is showing through.
\documentclass[10pt]{book}
\usepackage{xcolor}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
...
