For-loops with different iterations

Question

I have to print tickets for a theater. The seating plan of the theater is as follows:

Blocks (A right, A left, B right, B left, etc., through H)

Rows (Block A could have rows from 1 to 15, Block B from 1 to 20, and so on: they are not all the same in number)

Seat (Block A right row 1 could have seats from 1 to 4, Block A right row 2 from 1 to 22, and so on: again, not all the same in number)

I'm aware of the existence of for-loops in Latex, and I have successfully used them before, but I have the problem of how to tell the loop that it has to stop at row 15 if the Block is A, but it has to go to 20 if the Block is B, etc. Same for the seats (whereas if I solve the problem for the rows, I can solve it for the seats).

I though about putting the information about the number of rows per Block and the number of seats per row in a table, but then I don't know how to get the for loop to read the table. Or maybe the for is not right in this case? Maybe a while ... do would be more appropriate? But then I don't know how to implement that in Latex.

Answer 1

Using the pgffor package

One possibility:

\documentclass{article}
\usepackage{pgffor}

\begin{document}

\foreach \block/\rows in {
    A right/{4,22,31},
    A left/{4,5},
    B right/{10,4,3,4,5},
    } {
    \foreach \seats [count=\row] in \rows {
        \foreach \seat in {1, ..., \seats} {
            
            Block: \block\  Row: \row, Seat:\seat
        }
    }
}
\end{document}

Each block is defined using a block name and a list of the row sizes.

Answer 2

Since the OP gave no indication that a row's seat number may begin with something other than 1, I assumed that, but could change accordingly. Syntax:

\printtickets{<section name> : <row 1 seats>, <row 2 seats>,.../ ...}

The MWE:

\documentclass[12pt]{article}
\usepackage{listofitems,pgffor,stackengine}
\usepackage[margin=.5cm]{geometry}
\newcommand\printtickets[1]{\noindent%
  \setsepchar[@]{/@:@,}%
  \readlist*\seatcount{#1}%
  \foreachitem\x\in\seatcount[]{%
    \foreach\y in {1,...,{\listlen\seatcount[\xcnt,2]}}{%
      \foreach\z in {1,...,{\seatcount[\xcnt,2,\y]}}{%
        \addstackgap[1pt]{\fbox{\makebox[1in]{%
          \Longstack{Block~\seatcount[\xcnt,1] Row~\y{} Seat~\z}}}}\kern3pt\allowbreak%
      }%
    }%
  }%
}
\begin{document}
\sloppy
\printtickets{
  A right : 3,5,7     / 
  A left  : 3,5,6     /
  B right : 4,5,6,9,11/
  B left  : 4,5,6,9,11
}
\end{document}

Answer 3

something like this

\documentclass{article}

\makeatletter

\def\seats#1#2#3#4{%
\edef\minrow{\beforedash#2-\relax}%
\edef\maxrow{\afterdash#2-#2-\relax}%
\tickets{#1}\minrow\maxrow{#3}{#4}%
}
\def\beforedash#1-#2\relax{#1}
\def\afterdash#1-#2-#3\relax{#2}
\def\tickets#1#2#3#4#5{%
\count@#4 %
\loop
Block: #1, Row: \number#2, Seat: \the\count@\par
\ifnum\count@<#5 %
\advance\count@ 1 %
\repeat
\ifnum#2=#3 %
 \expandafter\@gobble
\else
  \expandafter\@firstofone
\fi
{\tickets{#1}{\numexpr#2+1\relax}{#3}{#4}{#5}}}

\begin{document}

%     block    row   low high      
\seats{A Left} {2-6} {1}  {10}
\seats{A Left} {1}   {2}  {8}
\seats{B Right}{1-8} {1}  {12}
\seats{B Right} {9}  {10}  {12}
\seats{B Right} {10} {10}  {12}


\end{document}