YES Problem: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) lastbit(0()) -> 0() lastbit(s(0())) -> s(0()) lastbit(s(s(x))) -> lastbit(x) zero(0()) -> true() zero(s(x)) -> false() conv(x) -> conviter(x,cons(0(),nil())) conviter(x,l) -> if(zero(x),x,l) if(true(),x,l) -> l if(false(),x,l) -> conviter(half(x),cons(lastbit(x),l)) Proof: DP Processor: DPs: half#(s(s(x))) -> half#(x) lastbit#(s(s(x))) -> lastbit#(x) conv#(x) -> conviter#(x,cons(0(),nil())) conviter#(x,l) -> zero#(x) conviter#(x,l) -> if#(zero(x),x,l) if#(false(),x,l) -> lastbit#(x) if#(false(),x,l) -> half#(x) if#(false(),x,l) -> conviter#(half(x),cons(lastbit(x),l)) TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) lastbit(0()) -> 0() lastbit(s(0())) -> s(0()) lastbit(s(s(x))) -> lastbit(x) zero(0()) -> true() zero(s(x)) -> false() conv(x) -> conviter(x,cons(0(),nil())) conviter(x,l) -> if(zero(x),x,l) if(true(),x,l) -> l if(false(),x,l) -> conviter(half(x),cons(lastbit(x),l)) TDG Processor: DPs: half#(s(s(x))) -> half#(x) lastbit#(s(s(x))) -> lastbit#(x) conv#(x) -> conviter#(x,cons(0(),nil())) conviter#(x,l) -> zero#(x) conviter#(x,l) -> if#(zero(x),x,l) if#(false(),x,l) -> lastbit#(x) if#(false(),x,l) -> half#(x) if#(false(),x,l) -> conviter#(half(x),cons(lastbit(x),l)) TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) lastbit(0()) -> 0() lastbit(s(0())) -> s(0()) lastbit(s(s(x))) -> lastbit(x) zero(0()) -> true() zero(s(x)) -> false() conv(x) -> conviter(x,cons(0(),nil())) conviter(x,l) -> if(zero(x),x,l) if(true(),x,l) -> l if(false(),x,l) -> conviter(half(x),cons(lastbit(x),l)) graph: if#(false(),x,l) -> conviter#(half(x),cons(lastbit(x),l)) -> conviter#(x,l) -> if#(zero(x),x,l) if#(false(),x,l) -> conviter#(half(x),cons(lastbit(x),l)) -> conviter#(x,l) -> zero#(x) if#(false(),x,l) -> lastbit#(x) -> lastbit#(s(s(x))) -> lastbit#(x) if#(false(),x,l) -> half#(x) -> half#(s(s(x))) -> half#(x) conviter#(x,l) -> if#(zero(x),x,l) -> if#(false(),x,l) -> conviter#(half(x),cons(lastbit(x),l)) conviter#(x,l) -> if#(zero(x),x,l) -> if#(false(),x,l) -> half#(x) conviter#(x,l) -> if#(zero(x),x,l) -> if#(false(),x,l) -> lastbit#(x) conv#(x) -> conviter#(x,cons(0(),nil())) -> conviter#(x,l) -> if#(zero(x),x,l) conv#(x) -> conviter#(x,cons(0(),nil())) -> conviter#(x,l) -> zero#(x) lastbit#(s(s(x))) -> lastbit#(x) -> lastbit#(s(s(x))) -> lastbit#(x) half#(s(s(x))) -> half#(x) -> half#(s(s(x))) -> half#(x) SCC Processor: #sccs: 3 #rules: 4 #arcs: 11/64 DPs: if#(false(),x,l) -> conviter#(half(x),cons(lastbit(x),l)) conviter#(x,l) -> if#(zero(x),x,l) TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) lastbit(0()) -> 0() lastbit(s(0())) -> s(0()) lastbit(s(s(x))) -> lastbit(x) zero(0()) -> true() zero(s(x)) -> false() conv(x) -> conviter(x,cons(0(),nil())) conviter(x,l) -> if(zero(x),x,l) if(true(),x,l) -> l if(false(),x,l) -> conviter(half(x),cons(lastbit(x),l)) Matrix Interpretation Processor: dim=1 interpretation: [if#](x0, x1, x2) = 2x0 + x1 + 2x2, [conviter#](x0, x1) = 2x0 + 2x1 + 1/2, [if](x0, x1, x2) = 2x1 + x2 + 5/2, [conviter](x0, x1) = 2x0 + x1 + 5/2, [cons](x0, x1) = x1, [nil] = 1/2, [conv](x0) = 2x0 + 7/2, [false] = 1/2, [true] = 0, [zero](x0) = 1/2x0, [lastbit](x0) = 5/2, [s](x0) = 3x0 + 1, [half](x0) = 1/2x0, [0] = 0 orientation: if#(false(),x,l) = 2l + x + 1 >= 2l + x + 1/2 = conviter#(half(x),cons(lastbit(x),l)) conviter#(x,l) = 2l + 2x + 1/2 >= 2l + 2x = if#(zero(x),x,l) half(0()) = 0 >= 0 = 0() half(s(0())) = 1/2 >= 0 = 0() half(s(s(x))) = 9/2x + 2 >= 3/2x + 1 = s(half(x)) lastbit(0()) = 5/2 >= 0 = 0() lastbit(s(0())) = 5/2 >= 1 = s(0()) lastbit(s(s(x))) = 5/2 >= 5/2 = lastbit(x) zero(0()) = 0 >= 0 = true() zero(s(x)) = 3/2x + 1/2 >= 1/2 = false() conv(x) = 2x + 7/2 >= 2x + 3 = conviter(x,cons(0(),nil())) conviter(x,l) = l + 2x + 5/2 >= l + 2x + 5/2 = if(zero(x),x,l) if(true(),x,l) = l + 2x + 5/2 >= l = l if(false(),x,l) = l + 2x + 5/2 >= l + x + 5/2 = conviter(half(x),cons(lastbit(x),l)) problem: DPs: TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) lastbit(0()) -> 0() lastbit(s(0())) -> s(0()) lastbit(s(s(x))) -> lastbit(x) zero(0()) -> true() zero(s(x)) -> false() conv(x) -> conviter(x,cons(0(),nil())) conviter(x,l) -> if(zero(x),x,l) if(true(),x,l) -> l if(false(),x,l) -> conviter(half(x),cons(lastbit(x),l)) Qed DPs: half#(s(s(x))) -> half#(x) TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) lastbit(0()) -> 0() lastbit(s(0())) -> s(0()) lastbit(s(s(x))) -> lastbit(x) zero(0()) -> true() zero(s(x)) -> false() conv(x) -> conviter(x,cons(0(),nil())) conviter(x,l) -> if(zero(x),x,l) if(true(),x,l) -> l if(false(),x,l) -> conviter(half(x),cons(lastbit(x),l)) KBO Processor: argument filtering: pi(0) = [] pi(half) = 0 pi(s) = [0] pi(lastbit) = 0 pi(zero) = [0] pi(true) = [] pi(false) = [] pi(conv) = [0] pi(nil) = [] pi(cons) = 1 pi(conviter) = 1 pi(if) = 2 pi(half#) = 0 weight function: w0 = 1 w(if) = w(cons) = w(nil) = w(conv) = w(false) = w(true) = w(zero) = w( lastbit) = w(0) = 1 w(half#) = w(conviter) = w(s) = w(half) = 0 precedence: half# ~ nil ~ conv ~ false ~ true ~ s > if ~ conviter ~ cons ~ zero ~ lastbit ~ half ~ 0 problem: DPs: TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) lastbit(0()) -> 0() lastbit(s(0())) -> s(0()) lastbit(s(s(x))) -> lastbit(x) zero(0()) -> true() zero(s(x)) -> false() conv(x) -> conviter(x,cons(0(),nil())) conviter(x,l) -> if(zero(x),x,l) if(true(),x,l) -> l if(false(),x,l) -> conviter(half(x),cons(lastbit(x),l)) Qed DPs: lastbit#(s(s(x))) -> lastbit#(x) TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) lastbit(0()) -> 0() lastbit(s(0())) -> s(0()) lastbit(s(s(x))) -> lastbit(x) zero(0()) -> true() zero(s(x)) -> false() conv(x) -> conviter(x,cons(0(),nil())) conviter(x,l) -> if(zero(x),x,l) if(true(),x,l) -> l if(false(),x,l) -> conviter(half(x),cons(lastbit(x),l)) KBO Processor: argument filtering: pi(0) = [] pi(half) = 0 pi(s) = [0] pi(lastbit) = 0 pi(zero) = [0] pi(true) = [] pi(false) = [] pi(conv) = [0] pi(nil) = [] pi(cons) = 1 pi(conviter) = 1 pi(if) = 2 pi(lastbit#) = 0 weight function: w0 = 1 w(if) = w(cons) = w(nil) = w(conv) = w(false) = w(true) = w(zero) = w( lastbit) = w(0) = 1 w(lastbit#) = w(conviter) = w(s) = w(half) = 0 precedence: lastbit# ~ nil ~ conv ~ false ~ true ~ s > if ~ conviter ~ cons ~ zero ~ lastbit ~ half ~ 0 problem: DPs: TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) lastbit(0()) -> 0() lastbit(s(0())) -> s(0()) lastbit(s(s(x))) -> lastbit(x) zero(0()) -> true() zero(s(x)) -> false() conv(x) -> conviter(x,cons(0(),nil())) conviter(x,l) -> if(zero(x),x,l) if(true(),x,l) -> l if(false(),x,l) -> conviter(half(x),cons(lastbit(x),l)) Qed