# 1320.py

def codalbin (a,codifica=''):
  (sin,des)=a; cs=codifica+'0'; cd=codifica+'1'
  if isinstance(sin,list): u=codalbin(sin,cs)
  else: u={sin:cs}
  if isinstance(des,list): v=codalbin(des,cd)
  else: v={des:cd}
  u.update(v); return u

a=[['a',[['g','d'],['f','e']]],['b',['c','h']]]

cod=codalbin(a)
for x in sorted(cod): print (x,cod[x])