Success!
Schemes(2):
  snap(S,N,A,P)
  HasSameAddress(X,Y)
Facts(2):
  snap('12345','C. Brown','12 Apple','555-1234').
  snap('33333','Snoopy','12 Apple','555-1234').
Rules(1):
  HasSameAddress(X,Y) :- snap(A,X,B,C),snap(D,Y,B,E).
Queries(1):
  HasSameAddress('Snoopy',Who)?
Domain(6):
  '12 Apple'
  '12345'
  '33333'
  '555-1234'
  'C. Brown'
  'Snoopy'