Cfrgtkky

I want to write an algorithm in a latex. There are various ways to write, but I want to write in the way given below. I have tried but I am not able to do anything similar to the given in the image.

see my code:

documentclass{article}

usepackage[utf8]{inputenc}   



begin{document}



Algorithm \



Input : 



Output : \



1. $T leftarrow $ an set of size $S$ \

2. textbf{if} $x = 0$\



3. hspace{1cm} textbf{return}



end{document}

Question : Some of the problems, I am facing are the color of the background, line numbering, spacing etc

based on nice @CaptainNabla answer:

documentclass{article}

usepackage{geometry}

usepackage{enumitem}

usepackage[framemethod=tikz]{mdframed}



usepackage{lipsum}

begin{document}



begin{mdframed}[hidealllines=true,backgroundcolor=gray!20]

parindent=0pt

parskip=2pt  % <-- gives more spaces between paragraphs



underline{textsc{ALLSUBSETSUMS}$^#(S,u)$:}



medskip      % for additional vertical space 

 textsf{INPUT:} A set $S$ of $n$ positive integers and an upper bound integer $u$.



textsf{OUTPUT:} The set of all subset sums with cardinality information of $S$ up to $u$.

begin{enumerate}[nosep]

    item textbf{if} $S={x}$

    item hspace{1cm} textbf{return} ${(0,0),(x,1)}$

    item $T leftarrow$ an arbitrary subset of $S$ of size $[n/2]$

    item textbf{return} textsc{ALLSUBSETSUMS}$^{#}(T,u)bigoplus_u$textsc{ALLSUBSETSUMS}$^{#}(Ssetminus T,u)$

end{enumerate}

end{mdframed}



lipsum[1]



end{document}

gives:

The background color can be adjusted as stated here. Then its just a matter of playing around with some fonts:

documentclass{article}

usepackage[utf8]{inputenc}

usepackage[framemethod=tikz]{mdframed}



begin{document}



begin{mdframed}[hidealllines=true,backgroundcolor=gray!20]

noindent

underline{textsc{AllSubsetSums}(^#(S,u)):}\



noindenttextsf{INPUT:} A set (S) of (n) positive integers and an upper bound integer (u).\

textsf{OUTPUT:} The set of all subset sums with cardinality information of (S) up to (u).



begin{enumerate}

    item textbf{if} (S={x})

    item hspace{1cm} textbf{return} ({(0,0),(x,1)})

    item (T leftarrow) an arbitrary subset of (S) of size ([n/2])

    item textbf{return} textsc{AllSubsetSums}(^#(T,u)oplus_u)textsc{AllSubsetSums}(^#(Ssetminus T,u))

end{enumerate}

end{mdframed}



end{document}

which gives

Its not perfect and requires still a lot of fiddling, especially if you have a lot of different algorithms. Then it might be better to redefine the paragraph command...