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 ;
 pair zaaag ;
 zaaag = direction 0 of paaad ;
numeric xaaah ;
 xaaah = angle zaaag ;
pair zaaai ;
 zaaai = dir xaaah ;
pair zaaaj ;
 zaaaj = 1cm * zaaai;
pair zaaak ;
 zaaak = zaaae + zaaaj;
path paaal ;
 paaal:=zaaae -- zaaak;
pen qaaam ;
 qaaam = pencircle scaled 1bp ;
drawarrow paaal   withpen qaaam   ;
 pair zaaan ;
 zaaan = point 0.5 of paaad ;
pair zaaao ;
 zaaao = direction 0.5 of paaad ;
numeric xaaap ;
 xaaap = angle zaaao ;
pair zaaaq ;
 zaaaq = dir xaaap ;
pair zaaar ;
 zaaar = 1cm * zaaaq;
pair zaaas ;
 zaaas = zaaan + zaaar;
path paaat ;
 paaat:=zaaan -- zaaas;
pen qaaau ;
 drawarrow paaat   withpen qaaam   ;
 pair zaaav ;
 zaaav = point 1.0 of paaad ;
pair zaaaw ;
 zaaaw = direction 1.0 of paaad ;
numeric xaaax ;
 xaaax = angle zaaaw ;
pair zaaay ;
 zaaay = dir xaaax ;
pair zaaaz ;
 zaaaz = 1cm * zaaay;
pair zaaba ;
 zaaba = zaaav + zaaaz;
path paabb ;
 paabb:=zaaav -- zaaba;
pen qaabc ;
 drawarrow paabb   withpen qaaam   ;
 currentpicture := currentpicture shifted 
                      -llcorner currentpicture shifted (1cm,2cm);
    endfig;
     end;