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

beginfig(1)
numeric xaaab ;
 xaaab = -1.0 * 1cm;
pair zaaac ;
 zaaac = ( xaaab , 1cm ) ;
pair zaaad ;
 zaaad = ( 0 , 1cm ) ;
pair zaaae ;
 zaaae = ( 1cm , 1cm ) ;
pair zaaaf ;
 zaaaf = ( xaaab , 0 ) ;
pair zaaag ;
 zaaag = ( 0 , 0 ) ;
pair zaaah ;
 zaaah = ( 1cm , 0 ) ;
path paaai ;
 paaai:=zaaaf -- zaaac;
draw paaai     ;
 path paaaj ;
 paaaj:=zaaaf -- zaaad;
draw paaaj     ;
 path paaak ;
 paaak:=zaaaf -- zaaae;
draw paaak     ;
 path paaal ;
 paaal:=zaaag -- zaaac;
draw paaal     ;
 path paaam ;
 paaam:=zaaag -- zaaad;
draw paaam     ;
 path paaan ;
 paaan:=zaaag -- zaaae;
draw paaan     ;
 path paaao ;
 paaao:=zaaah -- zaaac;
draw paaao     ;
 path paaap ;
 paaap:=zaaah -- zaaad;
draw paaap     ;
 path paaaq ;
 paaaq:=zaaah -- zaaae;
draw paaaq     ;
 picture Paaar ;
 Paaar:=btex $a$  etex ;
pair zaaas ;
 zaaas = ( 0 , 1.0 ) ;
pair zaaat ;
 zaaat = 3bp * zaaas;
picture Paaau ;
 Paaau:=Paaar shifted zaaac ;
pair zaaav ;
 zaaav = llcorner Paaar ;
pair zaaaw ;
 zaaaw = lrcorner Paaar ;
pair zaaax ;
 zaaax = ( 0.5 ) [ zaaav , zaaaw ] ;
pair zaaay ;
 zaaay = -1.0 * zaaax;
picture Paaaz ;
 Paaaz:=Paaau shifted zaaay ;
picture Paaba ;
 Paaba:=Paaaz shifted zaaat ;
draw Paaba     ;
 pen qaabb ;
 qaabb = pencircle scaled 3bp ;
draw zaaac   withpen qaabb   ;
 picture Paabc ;
 Paabc:=btex $a'$  etex ;
pair zaabd ;
 zaabd = ( 0 , -1.0 ) ;
pair zaabe ;
 zaabe = 3bp * zaabd;
picture Paabf ;
 Paabf:=Paabc shifted zaaaf ;
pair zaabg ;
 zaabg = ulcorner Paabc ;
pair zaabh ;
 zaabh = urcorner Paabc ;
pair zaabi ;
 zaabi = ( 0.5 ) [ zaabg , zaabh ] ;
pair zaabj ;
 zaabj = -1.0 * zaabi;
picture Paabk ;
 Paabk:=Paabf shifted zaabj ;
picture Paabl ;
 Paabl:=Paabk shifted zaabe ;
draw Paabl     ;
 pen qaabm ;
 draw zaaaf   withpen qaabb   ;
 picture Paabn ;
 Paabn:=btex $b$  etex ;
pair zaabo ;
 pair zaabp ;
 picture Paabq ;
 Paabq:=Paabn shifted zaaad ;
pair zaabr ;
 zaabr = llcorner Paabn ;
pair zaabs ;
 zaabs = lrcorner Paabn ;
pair zaabt ;
 zaabt = ( 0.5 ) [ zaabr , zaabs ] ;
pair zaabu ;
 zaabu = -1.0 * zaabt;
picture Paabv ;
 Paabv:=Paabq shifted zaabu ;
picture Paabw ;
 Paabw:=Paabv shifted zaaat ;
draw Paabw     ;
 pen qaabx ;
 draw zaaad   withpen qaabb   ;
 picture Paaby ;
 Paaby:=btex $b'$  etex ;
pair zaabz ;
 pair zaaca ;
 picture Paacb ;
 Paacb:=Paaby shifted zaaag ;
pair zaacc ;
 zaacc = ulcorner Paaby ;
pair zaacd ;
 zaacd = urcorner Paaby ;
pair zaace ;
 zaace = ( 0.5 ) [ zaacc , zaacd ] ;
pair zaacf ;
 zaacf = -1.0 * zaace;
picture Paacg ;
 Paacg:=Paacb shifted zaacf ;
picture Paach ;
 Paach:=Paacg shifted zaabe ;
draw Paach     ;
 pen qaaci ;
 draw zaaag   withpen qaabb   ;
 picture Paacj ;
 Paacj:=btex $c$  etex ;
pair zaack ;
 pair zaacl ;
 picture Paacm ;
 Paacm:=Paacj shifted zaaae ;
pair zaacn ;
 zaacn = llcorner Paacj ;
pair zaaco ;
 zaaco = lrcorner Paacj ;
pair zaacp ;
 zaacp = ( 0.5 ) [ zaacn , zaaco ] ;
pair zaacq ;
 zaacq = -1.0 * zaacp;
picture Paacr ;
 Paacr:=Paacm shifted zaacq ;
picture Paacs ;
 Paacs:=Paacr shifted zaaat ;
draw Paacs     ;
 pen qaact ;
 draw zaaae   withpen qaabb   ;
 picture Paacu ;
 Paacu:=btex $c'$  etex ;
pair zaacv ;
 pair zaacw ;
 picture Paacx ;
 Paacx:=Paacu shifted zaaah ;
pair zaacy ;
 zaacy = ulcorner Paacu ;
pair zaacz ;
 zaacz = urcorner Paacu ;
pair zaada ;
 zaada = ( 0.5 ) [ zaacy , zaacz ] ;
pair zaadb ;
 zaadb = -1.0 * zaada;
picture Paadc ;
 Paadc:=Paacx shifted zaadb ;
picture Paadd ;
 Paadd:=Paadc shifted zaabe ;
draw Paadd     ;
 pen qaade ;
 draw zaaah   withpen qaabb   ;
 currentpicture := currentpicture shifted 
                      -llcorner currentpicture shifted (1cm,2cm);
    endfig;
     end;