YES Problem: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) inc(0()) -> 0() inc(s(x)) -> s(inc(x)) log(x) -> log2(x,0()) log2(x,y) -> if(le(x,s(0())),x,inc(y)) if(true(),x,s(y)) -> y if(false(),x,y) -> log2(half(x),y) Proof: DP Processor: DPs: half#(s(s(x))) -> half#(x) le#(s(x),s(y)) -> le#(x,y) inc#(s(x)) -> inc#(x) log#(x) -> log2#(x,0()) log2#(x,y) -> inc#(y) log2#(x,y) -> le#(x,s(0())) log2#(x,y) -> if#(le(x,s(0())),x,inc(y)) if#(false(),x,y) -> half#(x) if#(false(),x,y) -> log2#(half(x),y) TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) inc(0()) -> 0() inc(s(x)) -> s(inc(x)) log(x) -> log2(x,0()) log2(x,y) -> if(le(x,s(0())),x,inc(y)) if(true(),x,s(y)) -> y if(false(),x,y) -> log2(half(x),y) TDG Processor: DPs: half#(s(s(x))) -> half#(x) le#(s(x),s(y)) -> le#(x,y) inc#(s(x)) -> inc#(x) log#(x) -> log2#(x,0()) log2#(x,y) -> inc#(y) log2#(x,y) -> le#(x,s(0())) log2#(x,y) -> if#(le(x,s(0())),x,inc(y)) if#(false(),x,y) -> half#(x) if#(false(),x,y) -> log2#(half(x),y) TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) inc(0()) -> 0() inc(s(x)) -> s(inc(x)) log(x) -> log2(x,0()) log2(x,y) -> if(le(x,s(0())),x,inc(y)) if(true(),x,s(y)) -> y if(false(),x,y) -> log2(half(x),y) graph: if#(false(),x,y) -> log2#(half(x),y) -> log2#(x,y) -> if#(le(x,s(0())),x,inc(y)) if#(false(),x,y) -> log2#(half(x),y) -> log2#(x,y) -> le#(x,s(0())) if#(false(),x,y) -> log2#(half(x),y) -> log2#(x,y) -> inc#(y) if#(false(),x,y) -> half#(x) -> half#(s(s(x))) -> half#(x) log2#(x,y) -> if#(le(x,s(0())),x,inc(y)) -> if#(false(),x,y) -> log2#(half(x),y) log2#(x,y) -> if#(le(x,s(0())),x,inc(y)) -> if#(false(),x,y) -> half#(x) log2#(x,y) -> inc#(y) -> inc#(s(x)) -> inc#(x) log2#(x,y) -> le#(x,s(0())) -> le#(s(x),s(y)) -> le#(x,y) log#(x) -> log2#(x,0()) -> log2#(x,y) -> if#(le(x,s(0())),x,inc(y)) log#(x) -> log2#(x,0()) -> log2#(x,y) -> le#(x,s(0())) log#(x) -> log2#(x,0()) -> log2#(x,y) -> inc#(y) inc#(s(x)) -> inc#(x) -> inc#(s(x)) -> inc#(x) le#(s(x),s(y)) -> le#(x,y) -> le#(s(x),s(y)) -> le#(x,y) half#(s(s(x))) -> half#(x) -> half#(s(s(x))) -> half#(x) SCC Processor: #sccs: 4 #rules: 5 #arcs: 14/81 DPs: if#(false(),x,y) -> log2#(half(x),y) log2#(x,y) -> if#(le(x,s(0())),x,inc(y)) TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) inc(0()) -> 0() inc(s(x)) -> s(inc(x)) log(x) -> log2(x,0()) log2(x,y) -> if(le(x,s(0())),x,inc(y)) if(true(),x,s(y)) -> y if(false(),x,y) -> log2(half(x),y) Matrix Interpretation Processor: dim=1 interpretation: [if#](x0, x1, x2) = 1/2x0 + 3/2x1 + 1, [log2#](x0, x1) = 3x0 + 2, [if](x0, x1, x2) = x2 + 1/2, [log2](x0, x1) = x1 + 1/2, [log](x0) = x0 + 1, [inc](x0) = x0, [false] = 3, [true] = 0, [le](x0, x1) = 3x0 + 2x1, [s](x0) = 2x0 + 1, [half](x0) = 1/2x0, [0] = 0 orientation: if#(false(),x,y) = 3/2x + 5/2 >= 3/2x + 2 = log2#(half(x),y) log2#(x,y) = 3x + 2 >= 3x + 2 = if#(le(x,s(0())),x,inc(y)) half(0()) = 0 >= 0 = 0() half(s(0())) = 1/2 >= 0 = 0() half(s(s(x))) = 2x + 3/2 >= x + 1 = s(half(x)) le(0(),y) = 2y >= 0 = true() le(s(x),0()) = 6x + 3 >= 3 = false() le(s(x),s(y)) = 6x + 4y + 5 >= 3x + 2y = le(x,y) inc(0()) = 0 >= 0 = 0() inc(s(x)) = 2x + 1 >= 2x + 1 = s(inc(x)) log(x) = x + 1 >= 1/2 = log2(x,0()) log2(x,y) = y + 1/2 >= y + 1/2 = if(le(x,s(0())),x,inc(y)) if(true(),x,s(y)) = 2y + 3/2 >= y = y if(false(),x,y) = y + 1/2 >= y + 1/2 = log2(half(x),y) problem: DPs: log2#(x,y) -> if#(le(x,s(0())),x,inc(y)) TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) inc(0()) -> 0() inc(s(x)) -> s(inc(x)) log(x) -> log2(x,0()) log2(x,y) -> if(le(x,s(0())),x,inc(y)) if(true(),x,s(y)) -> y if(false(),x,y) -> log2(half(x),y) SCC Processor: #sccs: 0 #rules: 0 #arcs: 2/1 DPs: half#(s(s(x))) -> half#(x) TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) inc(0()) -> 0() inc(s(x)) -> s(inc(x)) log(x) -> log2(x,0()) log2(x,y) -> if(le(x,s(0())),x,inc(y)) if(true(),x,s(y)) -> y if(false(),x,y) -> log2(half(x),y) Subterm Criterion Processor: simple projection: pi(half#) = 0 problem: DPs: TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) inc(0()) -> 0() inc(s(x)) -> s(inc(x)) log(x) -> log2(x,0()) log2(x,y) -> if(le(x,s(0())),x,inc(y)) if(true(),x,s(y)) -> y if(false(),x,y) -> log2(half(x),y) Qed DPs: le#(s(x),s(y)) -> le#(x,y) TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) inc(0()) -> 0() inc(s(x)) -> s(inc(x)) log(x) -> log2(x,0()) log2(x,y) -> if(le(x,s(0())),x,inc(y)) if(true(),x,s(y)) -> y if(false(),x,y) -> log2(half(x),y) Subterm Criterion Processor: simple projection: pi(le#) = 1 problem: DPs: TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) inc(0()) -> 0() inc(s(x)) -> s(inc(x)) log(x) -> log2(x,0()) log2(x,y) -> if(le(x,s(0())),x,inc(y)) if(true(),x,s(y)) -> y if(false(),x,y) -> log2(half(x),y) Qed DPs: inc#(s(x)) -> inc#(x) TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) inc(0()) -> 0() inc(s(x)) -> s(inc(x)) log(x) -> log2(x,0()) log2(x,y) -> if(le(x,s(0())),x,inc(y)) if(true(),x,s(y)) -> y if(false(),x,y) -> log2(half(x),y) Subterm Criterion Processor: simple projection: pi(inc#) = 0 problem: DPs: TRS: half(0()) -> 0() half(s(0())) -> 0() half(s(s(x))) -> s(half(x)) le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) inc(0()) -> 0() inc(s(x)) -> s(inc(x)) log(x) -> log2(x,0()) log2(x,y) -> if(le(x,s(0())),x,inc(y)) if(true(),x,s(y)) -> y if(false(),x,y) -> log2(half(x),y) Qed