#  The Kalotans are a tribe with a peculiar quirk. Their males always
#  tell the truth. Their females never make two consecutive true
#  statements, or two consecutive untrue statements.

#  An anthropologist (let's call him Worf) has begun to study
#  them. Worf does not yet know the Kalotan language. One day, he
#  meets a Kalotan (heterosexual) couple and their child Kibi. Worf
#  asks Kibi: ``Are you a boy?'' Kibi answers in Kalotan, which of
#  course Worf doesn't understand.

#  Worf turns to the parents (who know English) for explanation. One
#  of them says: ``Kibi said: `I am a boy.' '' The other adds: ``Kibi
#  is a girl. Kibi lied.''

#  Solve for the sex of the parents and Kibi.

  ae.findall {

    parentGender1 = ae.amb("M", "F")
    parentGender2 = ae.amb("M", "F")
    kibiGender = ae.amb("M", "F")
    kibiSaid = ae.amb("M", "F")
    kibiLied = ae.amb(true, false)
    
    ae.assert(parentGender1 != parentGender2)
    
    if kibiGender == "M"
      ae.assert(! kibiLied )
    end
    if kibiLied
      ae.assert( kibiSaid != kibiGender )
    else
      ae.assert( kibiSaid == kibiGender )
    end
    
    if parentGender1 == "M"
      ae.assert( kibiSaid == "M" )
    end

    if parentGender2 == "M"
      ae.assert( kibiGender == "F" )
      ae.assert( kibiLied )
    else
      ae.assert( (kibiGender == "F") ^ kibiLied )
    end
    
    [ parentGender1, parentGender2, kibiGender, kibiSaid, kibiLied ]
  }