(VAR fl d m i b b1 b2 b3 i1 i2 i3) (RULES start(i) -> busy(F, closed, stop, false, false, false, i) busy(BF, d, stop, b1, b2, b3, i) -> incorrect busy(FS, d, stop, b1, b2, b3, i) -> incorrect busy(fl, open, up, b1, b2, b3, i) -> incorrect busy(fl, open, down, b1, b2, b3, i) -> incorrect busy(B, closed, stop, false, false, false, empty) -> correct busy(F, closed, stop, false, false, false, empty) -> correct busy(S, closed, stop, false, false, false, empty) -> correct busy(B, closed, stop, false, false, false, newbuttons(i1,i2,i3,i)) -> idle(B, closed, stop, false, false, false, newbuttons(i1,i2,i3,i)) busy(F, closed, stop, false, false, false, newbuttons(i1,i2,i3,i)) -> idle(F, closed, stop, false, false, false, newbuttons(i1,i2,i3,i)) busy(S, closed, stop, false, false, false, newbuttons(i1,i2,i3,i)) -> idle(S, closed, stop, false, false, false, newbuttons(i1,i2,i3,i)) busy(B, open, stop, false, b2, b3, i) -> idle(B, closed, stop, false, b2, b3, i) busy(F, open, stop, b1, false, b3, i) -> idle(F, closed, stop, b1, false, b3, i) busy(S, open, stop, b1, b2, false, i) -> idle(S, closed, stop, b1, b2, false, i) busy(B, d, stop, true, b2, b3, i) -> idle(B, open, stop, false, b2, b3, i) busy(F, d, stop, b1, true, b3, i) -> idle(F, open, stop, b1, false, b3, i) busy(S, d, stop, b1, b2, true, i) -> idle(S, open, stop, b1, b2, false, i) busy(B, closed, down, b1, b2, b3, i) -> idle(B, closed, stop, b1, b2, b3, i) busy(S, closed, up, b1, b2, b3, i) -> idle(S, closed, stop, b1, b2, b3, i) busy(B, closed, up, true, b2, b3, i) -> idle(B, closed, stop, true, b2, b3, i) busy(F, closed, up, b1, true, b3, i) -> idle(F, closed, stop, b1, true, b3, i) busy(F, closed, down, b1, true, b3, i) -> idle(F, closed, stop, b1, true, b3, i) busy(S, closed, down, b1, b2, true, i) -> idle(S, closed, stop, b1, b2, true, i) busy(B, closed, up, false, b2, b3, i) -> idle(BF, closed, up, false, b2, b3, i) busy(F, closed, up, b1, false, b3, i) -> idle(FS, closed, up, b1, false, b3, i) busy(F, closed, down, b1, false, b3, i) -> idle(BF, closed, down, b1, false, b3, i) busy(S, closed, down, b1, b2, false, i) -> idle(FS, closed, down, b1, b2, false, i) busy(BF, closed, up, b1, b2, b3, i) -> idle(F, closed, up, b1, b2, b3, i) busy(BF, closed, down, b1, b2, b3, i) -> idle(B, closed, down, b1, b2, b3, i) busy(FS, closed, up, b1, b2, b3, i) -> idle(S, closed, up, b1, b2, b3, i) busy(FS, closed, down, b1, b2, b3, i) -> idle(F, closed, down, b1, b2, b3, i) busy(B, closed, stop, false, true, b3, i) -> idle(B, closed, up, false, true, b3, i) busy(B, closed, stop, false, false, true, i) -> idle(B, closed, up, false, false, true, i) busy(F, closed, stop, true, false, b3, i) -> idle(F, closed, down, true, false, b3, i) busy(F, closed, stop, false, false, true, i) -> idle(F, closed, up, false, false, true, i) busy(S, closed, stop, b1, true, false, i) -> idle(S, closed, down, b1, true, false, i) busy(S, closed, stop, true, false, false, i) -> idle(S, closed, down, true, false, false, i) idle(fl, d, m, b1, b2, b3, empty) -> busy(fl, d, m, b1, b2, b3, empty) idle(fl, d, m, b1, b2, b3, newbuttons(i1,i2,i3,i)) -> busy(fl, d, m, or(b1,i1), or(b2,i2), or(b3,i3), i) or(true, b) -> true or(false, b) -> b ) (COMMENT The rewrite system LIFT in \cite{G96}. )