module airportClassroom

abstract sig Equipment { loc : Location }

abstract sig Location { }

sig Plane, Vehicle extends Equipment {}

sig Runway, Taxiway, Gate extends Location {}

fact Rules {
  Runway.(~loc) in Plane
  all g: Gate | lone (g.(~loc) & Plane)
  (Plane.loc & Gate) in (Gate & Vehicle.loc)
}

pred show () {  }
run show for 10 but exactly 3 Gate, exactly 5 Plane