\documentclass[10pt,a4paper]{article}

% Packages
\usepackage{fancyhdr}           % For header and footer
\usepackage{multicol}           % Allows multicols in tables
\usepackage{tabularx}           % Intelligent column widths
\usepackage{tabulary}           % Used in header and footer
\usepackage{hhline}             % Border under tables
\usepackage{graphicx}           % For images
\usepackage{xcolor}             % For hex colours
%\usepackage[utf8x]{inputenc}    % For unicode character support
\usepackage[T1]{fontenc}        % Without this we get weird character replacements
\usepackage{colortbl}           % For coloured tables
\usepackage{setspace}           % For line height
\usepackage{lastpage}           % Needed for total page number
\usepackage{seqsplit}           % Splits long words.
%\usepackage{opensans}          % Can't make this work so far. Shame. Would be lovely.
\usepackage[normalem]{ulem}     % For underlining links
% Most of the following are not required for the majority
% of cheat sheets but are needed for some symbol support.
\usepackage{amsmath}            % Symbols
\usepackage{MnSymbol}           % Symbols
\usepackage{wasysym}            % Symbols
%\usepackage[english,german,french,spanish,italian]{babel}              % Languages

% Document Info
\author{Heavenel}
\pdfinfo{
  /Title (ds.pdf)
  /Creator (Cheatography)
  /Author (Heavenel)
  /Subject (ds Cheat Sheet)
}

% Lengths and widths
\addtolength{\textwidth}{6cm}
\addtolength{\textheight}{-1cm}
\addtolength{\hoffset}{-3cm}
\addtolength{\voffset}{-2cm}
\setlength{\tabcolsep}{0.2cm} % Space between columns
\setlength{\headsep}{-12pt} % Reduce space between header and content
\setlength{\headheight}{85pt} % If less, LaTeX automatically increases it
\renewcommand{\footrulewidth}{0pt} % Remove footer line
\renewcommand{\headrulewidth}{0pt} % Remove header line
\renewcommand{\seqinsert}{\ifmmode\allowbreak\else\-\fi} % Hyphens in seqsplit
% This two commands together give roughly
% the right line height in the tables
\renewcommand{\arraystretch}{1.3}
\onehalfspacing

% Commands
\newcommand{\SetRowColor}[1]{\noalign{\gdef\RowColorName{#1}}\rowcolor{\RowColorName}} % Shortcut for row colour
\newcommand{\mymulticolumn}[3]{\multicolumn{#1}{>{\columncolor{\RowColorName}}#2}{#3}} % For coloured multi-cols
\newcolumntype{x}[1]{>{\raggedright}p{#1}} % New column types for ragged-right paragraph columns
\newcommand{\tn}{\tabularnewline} % Required as custom column type in use

% Font and Colours
\definecolor{HeadBackground}{HTML}{333333}
\definecolor{FootBackground}{HTML}{666666}
\definecolor{TextColor}{HTML}{333333}
\definecolor{DarkBackground}{HTML}{A3A3A3}
\definecolor{LightBackground}{HTML}{F3F3F3}
\renewcommand{\familydefault}{\sfdefault}
\color{TextColor}

% Header and Footer
\pagestyle{fancy}
\fancyhead{} % Set header to blank
\fancyfoot{} % Set footer to blank
\fancyhead[L]{
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
    \SetRowColor{DarkBackground}
    \vspace{-7pt}
    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
    }
\end{tabulary}
\columnbreak
\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{ds Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{Heavenel} via \textcolor{DarkBackground}{\uline{cheatography.com/56321/cs/21369/}}}
\end{tabulary}
\end{multicols}}

\fancyfoot[L]{ \footnotesize
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
  \SetRowColor{FootBackground}
  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}Heavenel \\
  \uline{cheatography.com/heavenel} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Published 9th December, 2019.\\
   Updated 9th December, 2019.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}}  \\
  \SetRowColor{white}
  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
\end{tabulary}
\end{multicols}}




\begin{document}
\raggedright
\raggedcolumns

% Set font size to small. Switch to any value
% from this page to resize cheat sheet text:
% www.emerson.emory.edu/services/latex/latex_169.html
\footnotesize % Small font.

\begin{multicols*}{3}

\begin{tabularx}{5.377cm}{x{1.34379 cm} x{3.63321 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Logic}}  \tn
% Row 0
\SetRowColor{LightBackground}
Found & Stop testing when answer found \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Frequency & Order tests by frequency in switch and if-else structures \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
Switch & Substitute switch statement for if-else construct \tn 
% Row Count 6 (+ 2)
% Row 3
\SetRowColor{white}
Lookup Table & Substitute table lookups for complicated expressions \tn 
% Row Count 8 (+ 2)
% Row 4
\SetRowColor{LightBackground}
Lazy \seqsplit{Evaluation} & Only a few entries are ever used. Cache them for further use it may be better to compute values as needed. \tn 
% Row Count 12 (+ 4)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{1.44333 cm} x{3.53367 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Loops}}  \tn
% Row 0
\SetRowColor{LightBackground}
\seqsplit{Unswitching} & If the decision doesn't change while looping turn the loop inside out \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
Jamming & Combines two or more loops into one. Reduces loop overhead \tn 
% Row Count 6 (+ 3)
% Row 2
\SetRowColor{LightBackground}
Unrolling & Replaces a loop with straight-line code. With partial unrolling, two or more cases are handled inside \tn 
% Row Count 10 (+ 4)
% Row 3
\SetRowColor{white}
Minimize work & Put calculations that result in a constant before the loop \tn 
% Row Count 13 (+ 3)
% Row 4
\SetRowColor{LightBackground}
Sentinel Values & Special value that marks the end of an array. Replaces expensive compound tests \tn 
% Row Count 16 (+ 3)
% Row 5
\SetRowColor{white}
Busy Loop Inside & Putting the busiest loop on the inside \tn 
% Row Count 18 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{1.89126 cm} x{3.08574 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{General}}  \tn
% Row 0
\SetRowColor{LightBackground}
Routines - Inline & Rewrite routines inline \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Routine - Rewrite & Rewrite expensive system routines \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
Data tran – Float/Int & Replace f.p. numbers with integers \tn 
% Row Count 6 (+ 2)
% Row 3
\SetRowColor{white}
Data tran – Array Dims & Reduce array dimensions where possible \tn 
% Row Count 8 (+ 2)
% Row 4
\SetRowColor{LightBackground}
Data tran – Array Refs & Minimize array references \tn 
% Row Count 10 (+ 2)
% Row 5
\SetRowColor{white}
Data tran – Supp & Length index for arrays \tn 
% Row Count 12 (+ 2)
% Row 6
\SetRowColor{LightBackground}
Data tran – Caching & Save commonly used values, instead of recomputing or rereading them \tn 
% Row Count 15 (+ 3)
% Row 7
\SetRowColor{white}
Exp - Str redu & Replace expensive operations with cheaper ones \tn 
% Row Count 17 (+ 2)
% Row 8
\SetRowColor{LightBackground}
Exp - Compile Time & Initialize at compile time \tn 
% Row Count 19 (+ 2)
% Row 9
\SetRowColor{white}
Exp - Data Type & Use the proper data type for constants \tn 
% Row Count 21 (+ 2)
% Row 10
\SetRowColor{LightBackground}
Common Sub-Exp & Eliminate common subexpressions \tn 
% Row Count 23 (+ 2)
% Row 11
\SetRowColor{white}
Exp - Precompute & Better to look up values than to recompute them \tn 
% Row Count 25 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}


% That's all folks
\end{multicols*}

\end{document}