MAYBE Problem: f(x,y) -> cond(lt(x,y),x,y) cond(tt(),x,y) -> f(s(x),s(y)) lt(0(),y) -> tt() lt(s(x),s(y)) -> lt(x,y) Proof: DP Processor: DPs: f#(x,y) -> lt#(x,y) f#(x,y) -> cond#(lt(x,y),x,y) cond#(tt(),x,y) -> f#(s(x),s(y)) lt#(s(x),s(y)) -> lt#(x,y) TRS: f(x,y) -> cond(lt(x,y),x,y) cond(tt(),x,y) -> f(s(x),s(y)) lt(0(),y) -> tt() lt(s(x),s(y)) -> lt(x,y) Usable Rule Processor: DPs: f#(x,y) -> lt#(x,y) f#(x,y) -> cond#(lt(x,y),x,y) cond#(tt(),x,y) -> f#(s(x),s(y)) lt#(s(x),s(y)) -> lt#(x,y) TRS: lt(0(),y) -> tt() lt(s(x),s(y)) -> lt(x,y) Open