arrow tikz diagram

Question

I am trying to build the following diagram in latex with tikz:

However I only could find the following template to do a similar diagram:

    \documentclass{minimal}
     \usepackage{tikz}
      \usetikzlibrary{arrows,positioning} 
      \tikzset{
       %Define standard arrow tip
                >=stealth',
         %Define style for boxes
        punkt/.style={
       rectangle,
       rounded corners,
       draw=black, very thick,
       text width=6.5em,
       minimum height=2em,
       text centered},
     % Define arrow style
    pil/.style={
       ->,
       thick,
       shorten <=2pt,
       shorten >=2pt,}
        }

    \begin{document}
    \begin{tikzpicture}[node distance=1cm, auto,]
 %nodes
 \node[punkt] (market) {A};
  \node[punkt, inner sep=5pt,below=0.5cm of market]
 (formidler) {B};
  \node[punkt, inner sep=5pt,below=0.5cm of formidler]
  (forbottom) {C};
  % We make a dummy figure to make everything look nice.
  \node[above=of market] (dummy) {};
  \node[right=of dummy] (t) {2}
   edge[pil,bend left=45] (market.east) % edges are used to connect two nodes
    edge[pil, bend left=45] (formidler.east); % .east since we want
                                         % consistent style
    \node[left=of dummy] (g) {1}
     edge[pil, bend right=45] (market.west)
     edge[pil, bend right=45] (formidler.west)
     edge[pil, bend right=45] (forbottom.west)
     edge[pil,<->, bend left=45] node[auto] {0} (t);
     \end{tikzpicture}
      \end{document}

Which results the following:

Any idea on how to build the diagram horizontally rather than vertically?

Thanks in advance for your time.

Answer 1

Something like this:

Here's the code:

\documentclass[border=5mm,tikz]{standalone}
\usepackage{tikz}
\usetikzlibrary{arrows.meta}
\begin{document}

  \begin{tikzpicture}[
      box/.style={rectangle, draw, minimum width=14mm},
      double arrow/.style={double, -{Stealth[length=3mm, open]}}
     ]
     \foreach \alp [count=\c] in {A,...,F}{
         \node (\alp) at (2*\c,0)[box]{\alp};
     }
     \foreach \alp in {B,...,F} {
         \draw[double arrow](A.south) to [out=330, in=210] (\alp.south);
     }
  \end{tikzpicture}

\end{document}

EDIT

You can use the same idea with more complicated text and with labels under the arrows. Of course, you would have to change the width of the boxes if either the text or labels under the arrows were too wide. The slightly more complicated picture

was produced with the following small variation on the code above:

\documentclass[border=5mm,tikz]{standalone}
\usepackage{tikz}
\usetikzlibrary{arrows.meta}
\begin{document}

  \begin{tikzpicture}[
      box/.style={rectangle, draw, minimum width=14mm},
      double arrow/.style={double, -{Stealth[length=3mm, open]}}
     ]
     \foreach \alp [count=\c] in {text 1, text 2, text 3, text 4, text 5, text 6}{
         \node (\c) at (2*\c,0)[box]{\alp};
     }
     \foreach \alp [count=\c (from 2)] in {label a,label b,label c,label d,label e} {
     \draw[double arrow](1.south) to [out=330, in=210]  
          (\c.south)node[below,anchor=north west]{\alp};
     }
  \end{tikzpicture}

\end{document}

Just for completeness, here's how I'd do the diagram in the OP:

\documentclass[border=5mm,tikz]{standalone}
\usepackage{tikz}
\usetikzlibrary{arrows.meta}
\begin{document}

  \begin{tikzpicture}[
      box/.style={rectangle, rounded corners, thick, draw, minimum width=14mm},
     ]
     \node (1) at (-1,0){1};
     \node (2) at (1,0){2};
     \draw[<->](1) to [out=45, in=135] node[above]{0}(2);
     \foreach \alp [count=\c] in {A,B,C}{
         \node (\alp) at (0, -\c)[box]{\alp};
     }
     \foreach \alp in {A,B,C} {
         \draw[->](1.south west) to [out=225, in=135] (\alp.west);
         \if\alp C\else
           \draw[->](2.south east) to [out=315, in=45] (\alp.east);
         \fi
     }
  \end{tikzpicture}

\end{document}

to produce: