I am trying to draw the following block diagram using TikZ... No way :(
Can anyone help me?
Thank you so much!!!
I am trying to draw the following block diagram using TikZ... No way :(
Can anyone help me?
Thank you so much!!!
Try to understand this one. It's just one possibility.
\documentclass[tikz,border=2mm]{standalone}
\usetikzlibrary{positioning,arrows.meta}
\begin{document}
\begin{tikzpicture}[block1/.style={draw, minimum width=3cm, minimum height=1.8cm},
block2/.style={draw, minimum width=1cm, minimum height=.8cm},
>=Stealth]
\node[block1,label=above:lol] (b1) {lol};
\node[block1, right=5cm of b1] (b2) {lol2};
\path ([yshift=-3mm]b1.center)--([yshift=-3mm]b2.center) node [midway,block2] (b3) {lol3};
\draw[->] ([yshift=3mm]b1.east)--node[above] {c} ([yshift=3mm]b2.west);
\draw[->] ([yshift=-3mm]b1.east)--node[below] {a} (b3.west);
\draw[<-] ([yshift=-3mm]b2.west)--node[below] {b} (b3.east);
\draw[->] (b2.east)--++(0:1cm) node[right] {thanks!};
\end{tikzpicture}
\end{document}

Just for fun, with Plain TeX:
\obeylines\obeyspaces\let =\ \tt\catcode`\_=11
lol
_________ c ____________
| |---------------------------->| |
| lol | ______ | lol2 |----> thanks!
| |-----------> | lol3|-------->| |
|________| |_____| |____________|
a b
\bye
Alternatively, with eplain's verbatim facilities:
\input eplain
\verbatim|
lol
_________ c ____________
| |---------------------------->| |
| lol | ______ | lol2 |----> thanks!
| |-----------> | lol3|-------->| |
|________| |_____| |____________|
a b
|endverbatim
\bye
Both give the requested result:

The space between the underscore characters is a result of the font used (here, cmtt).