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  1. parent( mary, john ).
  2. parent( ann, mary ).
  3. female( mary).
  4. mother( x, y) :- parent( x, y), female( x).
  5. grandparent( x, y) :- parent( x, z), parent( z, y).
  6. ?- grandparent (ann,john)
Compilation error #stdin compilation error #stdout 0s 0KB
comments (?)
stdin 
Standard input is empty
compilation info 
prog.pl:6:4: syntax error: . or operator expected after expression
	1 error(s)
compilation failed
stdout 
Standard output is empty
https://ideone.com/3dRMb
language:
Prolog (gprolog 1.4.5)
created:
14 years ago
visibility:
public

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