input fks
verbatimtex
%&latex
\documentclass[9pt]{extarticle}
\usepackage[utf8]{inputenc}
\usepackage{fkssugar}
\begin{document}
etex
 
prologues:=3;
 
beginfig(1);
u:=3cm;
def rezistor(expr X,Y) =
   s:=3;
   t:=0.1;
   draw X--(X+1/s*(Y-X));
   draw t*u*unitvector(Y-X) rotated 90 shifted (X+1/s*(Y-X)) -- t*u*unitvector(Y-X) rotated -90 shifted (X+1/s*(Y-X)) -- t*u*unitvector(Y-X) rotated -90 shifted (X+(s-1)/s*(Y-X)) -- t*u*unitvector(Y-X) rotated 90 shifted (X+(s-1)/s*(Y-X)) -- cycle;
   draw (X+(s-1)/s*(Y-X))--Y;
enddef;
def rezistori(expr X,Y) =
   s:=3.8;
   t:=0.1;
   draw X--(X+1/s*(Y-X));
   draw t*u*unitvector(Y-X) rotated 90 shifted (X+1/s*(Y-X)) -- t*u*unitvector(Y-X) rotated -90 shifted (X+1/s*(Y-X)) -- t*u*unitvector(Y-X) rotated -90 shifted (X+(s-1)/s*(Y-X)) -- t*u*unitvector(Y-X) rotated 90 shifted (X+(s-1)/s*(Y-X)) -- cycle;
   draw (X+(s-1)/s*(Y-X))--Y;
enddef;

rezistor((u,u),(u,-u));
rezistor((u,u),(-u,u));
rezistor((-u,-u),(u,-u));
rezistor((-u,-u),(-u,u));
rezistori((u,u),origin);
rezistori((u,-u),origin);
rezistori((-u,u),origin);
rezistori((-u,-u),origin);

label.top("B",origin) scaled 1.5 shifted (0,.05u);
label.lft(("A") ,(-u,-u)) scaled 1.5 shifted (.5*(u,u));
endfig;
verbatimtex
\end{document}
etex
 
end;