input TEX;
prologues := 1;
%if scantokens(mpversion) < 1.200:
%   filenametemplate
%else:
%   outputtemplate :=
%fi
% "%j.eps";

beginfig(1)
pair zaaab ;
 zaaab = ( 0 , 0 ) ;
pair zaaac ;
 zaaac = ( 2cm , 0 ) ;
path paaad ;
 paaad:=zaaab { up }  .. zaaac { down }  ;
pair zaaae ;
 zaaae = point 0 of paaad ;
draw paaad     ;
 pair zaaaf ;
 zaaaf = direction 0 of paaad ;
numeric xaaag ;
 xaaag = angle zaaaf ;
pair zaaah ;
 zaaah = dir xaaag ;
pair zaaai ;
 zaaai = 1cm * zaaah;
pair zaaaj ;
 zaaaj = zaaae + zaaai;
path paaak ;
 paaak:=zaaae -- zaaaj;
pen qaaal ;
 qaaal = pencircle scaled 1bp ;
drawarrow paaak   withpen qaaal   ;
 pair zaaam ;
 zaaam = point 0.5 of paaad ;
pair zaaan ;
 zaaan = direction 0.5 of paaad ;
numeric xaaao ;
 xaaao = angle zaaan ;
pair zaaap ;
 zaaap = dir xaaao ;
pair zaaaq ;
 zaaaq = 1cm * zaaap;
pair zaaar ;
 zaaar = zaaam + zaaaq;
path paaas ;
 paaas:=zaaam -- zaaar;
drawarrow paaas   withpen qaaal   ;
 pair zaaat ;
 zaaat = point 1.0 of paaad ;
pair zaaau ;
 zaaau = direction 1.0 of paaad ;
numeric xaaav ;
 xaaav = angle zaaau ;
pair zaaaw ;
 zaaaw = dir xaaav ;
pair zaaax ;
 zaaax = 1cm * zaaaw;
pair zaaay ;
 zaaay = zaaat + zaaax;
path paaaz ;
 paaaz:=zaaat -- zaaay;
drawarrow paaaz   withpen qaaal   ;
 currentpicture := currentpicture shifted 
                      -llcorner currentpicture shifted (1cm,2cm);
    endfig;
     end;