YES Problem: le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) minus(0(),y) -> 0() minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) -> 0() if_minus(false(),s(x),y) -> s(minus(x,y)) gcd(0(),y) -> y gcd(s(x),0()) -> s(x) gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) Proof: DP Processor: DPs: le#(s(x),s(y)) -> le#(x,y) minus#(s(x),y) -> le#(s(x),y) minus#(s(x),y) -> if_minus#(le(s(x),y),s(x),y) if_minus#(false(),s(x),y) -> minus#(x,y) gcd#(s(x),s(y)) -> le#(y,x) gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) if_gcd#(true(),s(x),s(y)) -> minus#(x,y) if_gcd#(true(),s(x),s(y)) -> gcd#(minus(x,y),s(y)) if_gcd#(false(),s(x),s(y)) -> minus#(y,x) if_gcd#(false(),s(x),s(y)) -> gcd#(minus(y,x),s(x)) TRS: le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) minus(0(),y) -> 0() minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) -> 0() if_minus(false(),s(x),y) -> s(minus(x,y)) gcd(0(),y) -> y gcd(s(x),0()) -> s(x) gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) EDG Processor: DPs: le#(s(x),s(y)) -> le#(x,y) minus#(s(x),y) -> le#(s(x),y) minus#(s(x),y) -> if_minus#(le(s(x),y),s(x),y) if_minus#(false(),s(x),y) -> minus#(x,y) gcd#(s(x),s(y)) -> le#(y,x) gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) if_gcd#(true(),s(x),s(y)) -> minus#(x,y) if_gcd#(true(),s(x),s(y)) -> gcd#(minus(x,y),s(y)) if_gcd#(false(),s(x),s(y)) -> minus#(y,x) if_gcd#(false(),s(x),s(y)) -> gcd#(minus(y,x),s(x)) TRS: le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) minus(0(),y) -> 0() minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) -> 0() if_minus(false(),s(x),y) -> s(minus(x,y)) gcd(0(),y) -> y gcd(s(x),0()) -> s(x) gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) graph: if_gcd#(false(),s(x),s(y)) -> gcd#(minus(y,x),s(x)) -> gcd#(s(x),s(y)) -> le#(y,x) if_gcd#(false(),s(x),s(y)) -> gcd#(minus(y,x),s(x)) -> gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) if_gcd#(false(),s(x),s(y)) -> minus#(y,x) -> minus#(s(x),y) -> le#(s(x),y) if_gcd#(false(),s(x),s(y)) -> minus#(y,x) -> minus#(s(x),y) -> if_minus#(le(s(x),y),s(x),y) if_gcd#(true(),s(x),s(y)) -> gcd#(minus(x,y),s(y)) -> gcd#(s(x),s(y)) -> le#(y,x) if_gcd#(true(),s(x),s(y)) -> gcd#(minus(x,y),s(y)) -> gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) if_gcd#(true(),s(x),s(y)) -> minus#(x,y) -> minus#(s(x),y) -> le#(s(x),y) if_gcd#(true(),s(x),s(y)) -> minus#(x,y) -> minus#(s(x),y) -> if_minus#(le(s(x),y),s(x),y) gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) -> if_gcd#(true(),s(x),s(y)) -> minus#(x,y) gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) -> if_gcd#(true(),s(x),s(y)) -> gcd#(minus(x,y),s(y)) gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) -> if_gcd#(false(),s(x),s(y)) -> minus#(y,x) gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) -> if_gcd#(false(),s(x),s(y)) -> gcd#(minus(y,x),s(x)) gcd#(s(x),s(y)) -> le#(y,x) -> le#(s(x),s(y)) -> le#(x,y) if_minus#(false(),s(x),y) -> minus#(x,y) -> minus#(s(x),y) -> le#(s(x),y) if_minus#(false(),s(x),y) -> minus#(x,y) -> minus#(s(x),y) -> if_minus#(le(s(x),y),s(x),y) minus#(s(x),y) -> if_minus#(le(s(x),y),s(x),y) -> if_minus#(false(),s(x),y) -> minus#(x,y) minus#(s(x),y) -> le#(s(x),y) -> le#(s(x),s(y)) -> le#(x,y) le#(s(x),s(y)) -> le#(x,y) -> le#(s(x),s(y)) -> le#(x,y) SCC Processor: #sccs: 3 #rules: 6 #arcs: 18/100 DPs: if_gcd#(false(),s(x),s(y)) -> gcd#(minus(y,x),s(x)) gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) if_gcd#(true(),s(x),s(y)) -> gcd#(minus(x,y),s(y)) TRS: le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) minus(0(),y) -> 0() minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) -> 0() if_minus(false(),s(x),y) -> s(minus(x,y)) gcd(0(),y) -> y gcd(s(x),0()) -> s(x) gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) Matrix Interpretation Processor: dimension: 1 interpretation: [if_gcd#](x0, x1, x2) = x1 + x2, [gcd#](x0, x1) = x0 + x1, [if_gcd](x0, x1, x2) = x1 + x2, [gcd](x0, x1) = x0 + x1 + 1, [if_minus](x0, x1, x2) = x1, [minus](x0, x1) = x0, [false] = 0, [s](x0) = x0 + 1, [true] = 0, [le](x0, x1) = 1, [0] = 0 orientation: if_gcd#(false(),s(x),s(y)) = x + y + 2 >= x + y + 1 = gcd#(minus(y,x),s(x)) gcd#(s(x),s(y)) = x + y + 2 >= x + y + 2 = if_gcd#(le(y,x),s(x),s(y)) if_gcd#(true(),s(x),s(y)) = x + y + 2 >= x + y + 1 = gcd#(minus(x,y),s(y)) le(0(),y) = 1 >= 0 = true() le(s(x),0()) = 1 >= 0 = false() le(s(x),s(y)) = 1 >= 1 = le(x,y) minus(0(),y) = 0 >= 0 = 0() minus(s(x),y) = x + 1 >= x + 1 = if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) = x + 1 >= 0 = 0() if_minus(false(),s(x),y) = x + 1 >= x + 1 = s(minus(x,y)) gcd(0(),y) = y + 1 >= y = y gcd(s(x),0()) = x + 2 >= x + 1 = s(x) gcd(s(x),s(y)) = x + y + 3 >= x + y + 2 = if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) = x + y + 2 >= x + y + 2 = gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) = x + y + 2 >= x + y + 2 = gcd(minus(y,x),s(x)) problem: DPs: gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) TRS: le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) minus(0(),y) -> 0() minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) -> 0() if_minus(false(),s(x),y) -> s(minus(x,y)) gcd(0(),y) -> y gcd(s(x),0()) -> s(x) gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) Matrix Interpretation Processor: dimension: 1 interpretation: [if_gcd#](x0, x1, x2) = 0, [gcd#](x0, x1) = 1, [if_gcd](x0, x1, x2) = 0, [gcd](x0, x1) = x1, [if_minus](x0, x1, x2) = 0, [minus](x0, x1) = 0, [false] = 0, [s](x0) = 0, [true] = 0, [le](x0, x1) = 0, [0] = 0 orientation: gcd#(s(x),s(y)) = 1 >= 0 = if_gcd#(le(y,x),s(x),s(y)) le(0(),y) = 0 >= 0 = true() le(s(x),0()) = 0 >= 0 = false() le(s(x),s(y)) = 0 >= 0 = le(x,y) minus(0(),y) = 0 >= 0 = 0() minus(s(x),y) = 0 >= 0 = if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) = 0 >= 0 = 0() if_minus(false(),s(x),y) = 0 >= 0 = s(minus(x,y)) gcd(0(),y) = y >= y = y gcd(s(x),0()) = 0 >= 0 = s(x) gcd(s(x),s(y)) = 0 >= 0 = if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) = 0 >= 0 = gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) = 0 >= 0 = gcd(minus(y,x),s(x)) problem: DPs: TRS: le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) minus(0(),y) -> 0() minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) -> 0() if_minus(false(),s(x),y) -> s(minus(x,y)) gcd(0(),y) -> y gcd(s(x),0()) -> s(x) gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) Qed DPs: minus#(s(x),y) -> if_minus#(le(s(x),y),s(x),y) if_minus#(false(),s(x),y) -> minus#(x,y) TRS: le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) minus(0(),y) -> 0() minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) -> 0() if_minus(false(),s(x),y) -> s(minus(x,y)) gcd(0(),y) -> y gcd(s(x),0()) -> s(x) gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) Subterm Criterion Processor: simple projection: pi(minus#) = 0 pi(if_minus#) = 1 problem: DPs: minus#(s(x),y) -> if_minus#(le(s(x),y),s(x),y) TRS: le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) minus(0(),y) -> 0() minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) -> 0() if_minus(false(),s(x),y) -> s(minus(x,y)) gcd(0(),y) -> y gcd(s(x),0()) -> s(x) gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) Matrix Interpretation Processor: dimension: 1 interpretation: [if_minus#](x0, x1, x2) = 0, [minus#](x0, x1) = x0, [if_gcd](x0, x1, x2) = x0, [gcd](x0, x1) = x1, [if_minus](x0, x1, x2) = x0, [minus](x0, x1) = 1, [false] = 1, [s](x0) = 1, [true] = 1, [le](x0, x1) = 1, [0] = 1 orientation: minus#(s(x),y) = 1 >= 0 = if_minus#(le(s(x),y),s(x),y) le(0(),y) = 1 >= 1 = true() le(s(x),0()) = 1 >= 1 = false() le(s(x),s(y)) = 1 >= 1 = le(x,y) minus(0(),y) = 1 >= 1 = 0() minus(s(x),y) = 1 >= 1 = if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) = 1 >= 1 = 0() if_minus(false(),s(x),y) = 1 >= 1 = s(minus(x,y)) gcd(0(),y) = y >= y = y gcd(s(x),0()) = 1 >= 1 = s(x) gcd(s(x),s(y)) = 1 >= 1 = if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) = 1 >= 1 = gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) = 1 >= 1 = gcd(minus(y,x),s(x)) problem: DPs: TRS: le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) minus(0(),y) -> 0() minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) -> 0() if_minus(false(),s(x),y) -> s(minus(x,y)) gcd(0(),y) -> y gcd(s(x),0()) -> s(x) gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) Qed DPs: le#(s(x),s(y)) -> le#(x,y) TRS: le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) minus(0(),y) -> 0() minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) -> 0() if_minus(false(),s(x),y) -> s(minus(x,y)) gcd(0(),y) -> y gcd(s(x),0()) -> s(x) gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) Subterm Criterion Processor: simple projection: pi(le#) = 1 problem: DPs: TRS: le(0(),y) -> true() le(s(x),0()) -> false() le(s(x),s(y)) -> le(x,y) minus(0(),y) -> 0() minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) -> 0() if_minus(false(),s(x),y) -> s(minus(x,y)) gcd(0(),y) -> y gcd(s(x),0()) -> s(x) gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) Qed