Starting on goal: Prolog$Goal(car=l("[]", "500", "=", "smartmul", l("()", l("[]", "50", ",", Prolog$Var(id=0L, instance=r5)))))
  Trying clause: "[]"(_1, "=", intmul, "()"("[]"(_2, ",", _3))) :- native
No match for clause.
  Trying clause: "[]"(_4, "=", intdiv, "()"("[]"(_5, ",", _6))) :- native
No match for clause.
  Trying clause: "[]"(_7, "=", intadd, "()"("[]"(_8, ",", _9))) :- native
No match for clause.
  Trying clause: "[]"(_10, "=", intminus, "()"("[]"(_11, ",", _12))) :- native
No match for clause.
  Trying clause: "[]"(_13, "=", smartmul, "()"("[]"(_14, ",", _15))) :- "[]"(_13, "=", intmul, "()"("[]"(_14, ",", _15)))
New goal: "[]"("500", "=", smartmul, "()"("[]"("50", ",", $x)))
Exception in native: java.lang.NumberFormatException: For input string: "$x"
   Trying clause: "[]"(_16, "=", intmul, "()"("[]"(_17, ",", _18))) :- native
Exception in native: java.lang.NumberFormatException: For input string: "$x"
 Native clause fails
   Trying clause: "[]"(_19, "=", intdiv, "()"("[]"(_20, ",", _21))) :- native
 No match for clause.
   Trying clause: "[]"(_22, "=", intadd, "()"("[]"(_23, ",", _24))) :- native
 No match for clause.
   Trying clause: "[]"(_25, "=", intminus, "()"("[]"(_26, ",", _27))) :- native
 No match for clause.
   Trying clause: "[]"(_28, "=", smartmul, "()"("[]"(_29, ",", _30))) :- "[]"(_28, "=", intmul, "()"("[]"(_29, ",", _30)))
 No match for clause.
   Trying clause: "[]"(_31, "=", smartmul, "()"("[]"(_32, ",", _33))) :- "[]"(_32, "=", intdiv, "()"("[]"(_31, ",", _33)))
 No match for clause.
   Trying clause: "[]"(_34, "=", smartmul, "()"("[]"(_35, ",", _36))) :- "[]"(_36, "=", intdiv, "()"("[]"(_34, ",", _35)))
 No match for clause.
   Trying clause: "[]"("[]"(not, "()"(true)), should, be, false)
 No match for clause.
   Trying clause: "[]"(mrshutco, is, a, human)
 No match for clause.
   Trying clause: "[]"("[]"(not, "()"(false)), should, be, true)
 No match for clause.
  Trying clause: "[]"(_37, "=", smartmul, "()"("[]"(_38, ",", _39))) :- "[]"(_38, "=", intdiv, "()"("[]"(_37, ",", _39)))
New goal: "[]"("500", "=", smartmul, "()"("[]"("50", ",", $x)))
Exception in native: java.lang.NumberFormatException: For input string: "$x"
   Trying clause: "[]"(_40, "=", intmul, "()"("[]"(_41, ",", _42))) :- native
 No match for clause.
   Trying clause: "[]"(_43, "=", intdiv, "()"("[]"(_44, ",", _45))) :- native
Exception in native: java.lang.NumberFormatException: For input string: "$x"
 Native clause fails
   Trying clause: "[]"(_46, "=", intadd, "()"("[]"(_47, ",", _48))) :- native
 No match for clause.
   Trying clause: "[]"(_49, "=", intminus, "()"("[]"(_50, ",", _51))) :- native
 No match for clause.
   Trying clause: "[]"(_52, "=", smartmul, "()"("[]"(_53, ",", _54))) :- "[]"(_52, "=", intmul, "()"("[]"(_53, ",", _54)))
 No match for clause.
   Trying clause: "[]"(_55, "=", smartmul, "()"("[]"(_56, ",", _57))) :- "[]"(_56, "=", intdiv, "()"("[]"(_55, ",", _57)))
 No match for clause.
   Trying clause: "[]"(_58, "=", smartmul, "()"("[]"(_59, ",", _60))) :- "[]"(_60, "=", intdiv, "()"("[]"(_58, ",", _59)))
 No match for clause.
   Trying clause: "[]"("[]"(not, "()"(true)), should, be, false)
 No match for clause.
   Trying clause: "[]"(mrshutco, is, a, human)
 No match for clause.
   Trying clause: "[]"("[]"(not, "()"(false)), should, be, true)
 No match for clause.
  Trying clause: "[]"(_61, "=", smartmul, "()"("[]"(_62, ",", _63))) :- "[]"(_63, "=", intdiv, "()"("[]"(_61, ",", _62)))
New goal: "[]"("500", "=", smartmul, "()"("[]"("50", ",", $x)))
   Trying clause: "[]"(_64, "=", intmul, "()"("[]"(_65, ",", _66))) :- native
 No match for clause.
   Trying clause: "[]"(_67, "=", intdiv, "()"("[]"(_68, ",", _69))) :- native
SUCCESS!