MAYBE Problem: lt(0(),s(x)) -> true() lt(x,0()) -> false() lt(s(x),s(y)) -> lt(x,y) minus(x,y) -> help(lt(y,x),x,y) help(true(),x,y) -> s(minus(x,s(y))) help(false(),x,y) -> 0() Proof: DP Processor: DPs: lt#(s(x),s(y)) -> lt#(x,y) minus#(x,y) -> lt#(y,x) minus#(x,y) -> help#(lt(y,x),x,y) help#(true(),x,y) -> minus#(x,s(y)) TRS: lt(0(),s(x)) -> true() lt(x,0()) -> false() lt(s(x),s(y)) -> lt(x,y) minus(x,y) -> help(lt(y,x),x,y) help(true(),x,y) -> s(minus(x,s(y))) help(false(),x,y) -> 0() TDG Processor: DPs: lt#(s(x),s(y)) -> lt#(x,y) minus#(x,y) -> lt#(y,x) minus#(x,y) -> help#(lt(y,x),x,y) help#(true(),x,y) -> minus#(x,s(y)) TRS: lt(0(),s(x)) -> true() lt(x,0()) -> false() lt(s(x),s(y)) -> lt(x,y) minus(x,y) -> help(lt(y,x),x,y) help(true(),x,y) -> s(minus(x,s(y))) help(false(),x,y) -> 0() graph: help#(true(),x,y) -> minus#(x,s(y)) -> minus#(x,y) -> help#(lt(y,x),x,y) help#(true(),x,y) -> minus#(x,s(y)) -> minus#(x,y) -> lt#(y,x) minus#(x,y) -> help#(lt(y,x),x,y) -> help#(true(),x,y) -> minus#(x,s(y)) minus#(x,y) -> lt#(y,x) -> lt#(s(x),s(y)) -> lt#(x,y) lt#(s(x),s(y)) -> lt#(x,y) -> lt#(s(x),s(y)) -> lt#(x,y) SCC Processor: #sccs: 2 #rules: 3 #arcs: 5/16 DPs: help#(true(),x,y) -> minus#(x,s(y)) minus#(x,y) -> help#(lt(y,x),x,y) TRS: lt(0(),s(x)) -> true() lt(x,0()) -> false() lt(s(x),s(y)) -> lt(x,y) minus(x,y) -> help(lt(y,x),x,y) help(true(),x,y) -> s(minus(x,s(y))) help(false(),x,y) -> 0() Open DPs: lt#(s(x),s(y)) -> lt#(x,y) TRS: lt(0(),s(x)) -> true() lt(x,0()) -> false() lt(s(x),s(y)) -> lt(x,y) minus(x,y) -> help(lt(y,x),x,y) help(true(),x,y) -> s(minus(x,s(y))) help(false(),x,y) -> 0() Subterm Criterion Processor: simple projection: pi(lt#) = 1 problem: DPs: TRS: lt(0(),s(x)) -> true() lt(x,0()) -> false() lt(s(x),s(y)) -> lt(x,y) minus(x,y) -> help(lt(y,x),x,y) help(true(),x,y) -> s(minus(x,s(y))) help(false(),x,y) -> 0() Qed