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     ;
 draw zaaaf   withpen qaabb   ;
 picture Paabm ;
 Paabm:=btex $b$  etex ;
picture Paabn ;
 Paabn:=Paabm shifted zaaad ;
pair zaabo ;
 zaabo = llcorner Paabm ;
pair zaabp ;
 zaabp = lrcorner Paabm ;
pair zaabq ;
 zaabq = ( 0.5 ) [ zaabo , zaabp ] ;
pair zaabr ;
 zaabr = -1.0 * zaabq;
picture Paabs ;
 Paabs:=Paabn shifted zaabr ;
picture Paabt ;
 Paabt:=Paabs shifted zaaat ;
draw Paabt     ;
 draw zaaad   withpen qaabb   ;
 picture Paabu ;
 Paabu:=btex $b'$  etex ;
picture Paabv ;
 Paabv:=Paabu shifted zaaag ;
pair zaabw ;
 zaabw = ulcorner Paabu ;
pair zaabx ;
 zaabx = urcorner Paabu ;
pair zaaby ;
 zaaby = ( 0.5 ) [ zaabw , zaabx ] ;
pair zaabz ;
 zaabz = -1.0 * zaaby;
picture Paaca ;
 Paaca:=Paabv shifted zaabz ;
picture Paacb ;
 Paacb:=Paaca shifted zaabe ;
draw Paacb     ;
 draw zaaag   withpen qaabb   ;
 picture Paacc ;
 Paacc:=btex $c$  etex ;
picture Paacd ;
 Paacd:=Paacc shifted zaaae ;
pair zaace ;
 zaace = llcorner Paacc ;
pair zaacf ;
 zaacf = lrcorner Paacc ;
pair zaacg ;
 zaacg = ( 0.5 ) [ zaace , zaacf ] ;
pair zaach ;
 zaach = -1.0 * zaacg;
picture Paaci ;
 Paaci:=Paacd shifted zaach ;
picture Paacj ;
 Paacj:=Paaci shifted zaaat ;
draw Paacj     ;
 draw zaaae   withpen qaabb   ;
 picture Paack ;
 Paack:=btex $c'$  etex ;
picture Paacl ;
 Paacl:=Paack shifted zaaah ;
pair zaacm ;
 zaacm = ulcorner Paack ;
pair zaacn ;
 zaacn = urcorner Paack ;
pair zaaco ;
 zaaco = ( 0.5 ) [ zaacm , zaacn ] ;
pair zaacp ;
 zaacp = -1.0 * zaaco;
picture Paacq ;
 Paacq:=Paacl shifted zaacp ;
picture Paacr ;
 Paacr:=Paacq shifted zaabe ;
draw Paacr     ;
 draw zaaah   withpen qaabb   ;
 currentpicture := currentpicture shifted 
                      -llcorner currentpicture shifted (1cm,2cm);
    endfig;
     end;