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) Arctic Interpretation Processor: dimension: 1 interpretation: [if#](x0, x1, x2) = x0 + -1x1 + -16, [log2#](x0, x1) = 1x0 + -1, [if](x0, x1, x2) = x0 + -1x1 + x2 + -1, [log2](x0, x1) = 1x0 + x1 + 1, [log](x0) = 1x0 + 15, [inc](x0) = x0, [false] = 1, [true] = 0, [le](x0, x1) = x0 + -4x1 + -16, [s](x0) = 2x0 + 2, [half](x0) = -2x0 + 0, [0] = 0 orientation: if#(false(),x,y) = -1x + 1 >= -1x + 1 = log2#(half(x),y) log2#(x,y) = 1x + -1 >= x + -2 = if#(le(x,s(0())),x,inc(y)) half(0()) = 0 >= 0 = 0() half(s(0())) = 0 >= 0 = 0() half(s(s(x))) = 2x + 2 >= x + 2 = s(half(x)) le(0(),y) = -4y + 0 >= 0 = true() le(s(x),0()) = 2x + 2 >= 1 = false() le(s(x),s(y)) = 2x + -2y + 2 >= x + -4y + -16 = le(x,y) inc(0()) = 0 >= 0 = 0() inc(s(x)) = 2x + 2 >= 2x + 2 = s(inc(x)) log(x) = 1x + 15 >= 1x + 1 = log2(x,0()) log2(x,y) = 1x + y + 1 >= x + y + -1 = if(le(x,s(0())),x,inc(y)) if(true(),x,s(y)) = -1x + 2y + 2 >= y = y if(false(),x,y) = -1x + y + 1 >= -1x + y + 1 = log2(half(x),y) problem: DPs: 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) 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