YES Problem: a(a(y,0()),0()) -> y c(c(y)) -> y c(a(c(c(y)),x)) -> a(c(c(c(a(x,0())))),y) Proof: DP Processor: DPs: c#(a(c(c(y)),x)) -> a#(x,0()) c#(a(c(c(y)),x)) -> c#(a(x,0())) c#(a(c(c(y)),x)) -> c#(c(a(x,0()))) c#(a(c(c(y)),x)) -> c#(c(c(a(x,0())))) c#(a(c(c(y)),x)) -> a#(c(c(c(a(x,0())))),y) TRS: a(a(y,0()),0()) -> y c(c(y)) -> y c(a(c(c(y)),x)) -> a(c(c(c(a(x,0())))),y) TDG Processor: DPs: c#(a(c(c(y)),x)) -> a#(x,0()) c#(a(c(c(y)),x)) -> c#(a(x,0())) c#(a(c(c(y)),x)) -> c#(c(a(x,0()))) c#(a(c(c(y)),x)) -> c#(c(c(a(x,0())))) c#(a(c(c(y)),x)) -> a#(c(c(c(a(x,0())))),y) TRS: a(a(y,0()),0()) -> y c(c(y)) -> y c(a(c(c(y)),x)) -> a(c(c(c(a(x,0())))),y) graph: c#(a(c(c(y)),x)) -> c#(c(c(a(x,0())))) -> c#(a(c(c(y)),x)) -> a#(c(c(c(a(x,0())))),y) c#(a(c(c(y)),x)) -> c#(c(c(a(x,0())))) -> c#(a(c(c(y)),x)) -> c#(c(c(a(x,0())))) c#(a(c(c(y)),x)) -> c#(c(c(a(x,0())))) -> c#(a(c(c(y)),x)) -> c#(c(a(x,0()))) c#(a(c(c(y)),x)) -> c#(c(c(a(x,0())))) -> c#(a(c(c(y)),x)) -> c#(a(x,0())) c#(a(c(c(y)),x)) -> c#(c(c(a(x,0())))) -> c#(a(c(c(y)),x)) -> a#(x,0()) c#(a(c(c(y)),x)) -> c#(c(a(x,0()))) -> c#(a(c(c(y)),x)) -> a#(c(c(c(a(x,0())))),y) c#(a(c(c(y)),x)) -> c#(c(a(x,0()))) -> c#(a(c(c(y)),x)) -> c#(c(c(a(x,0())))) c#(a(c(c(y)),x)) -> c#(c(a(x,0()))) -> c#(a(c(c(y)),x)) -> c#(c(a(x,0()))) c#(a(c(c(y)),x)) -> c#(c(a(x,0()))) -> c#(a(c(c(y)),x)) -> c#(a(x,0())) c#(a(c(c(y)),x)) -> c#(c(a(x,0()))) -> c#(a(c(c(y)),x)) -> a#(x,0()) c#(a(c(c(y)),x)) -> c#(a(x,0())) -> c#(a(c(c(y)),x)) -> a#(c(c(c(a(x,0())))),y) c#(a(c(c(y)),x)) -> c#(a(x,0())) -> c#(a(c(c(y)),x)) -> c#(c(c(a(x,0())))) c#(a(c(c(y)),x)) -> c#(a(x,0())) -> c#(a(c(c(y)),x)) -> c#(c(a(x,0()))) c#(a(c(c(y)),x)) -> c#(a(x,0())) -> c#(a(c(c(y)),x)) -> c#(a(x,0())) c#(a(c(c(y)),x)) -> c#(a(x,0())) -> c#(a(c(c(y)),x)) -> a#(x,0()) SCC Processor: #sccs: 1 #rules: 3 #arcs: 15/25 DPs: c#(a(c(c(y)),x)) -> c#(c(c(a(x,0())))) c#(a(c(c(y)),x)) -> c#(a(x,0())) c#(a(c(c(y)),x)) -> c#(c(a(x,0()))) TRS: a(a(y,0()),0()) -> y c(c(y)) -> y c(a(c(c(y)),x)) -> a(c(c(c(a(x,0())))),y) Matrix Interpretation Processor: dim=3 interpretation: [c#](x0) = [2 0 0]x0, [1 0 1] [0] [c](x0) = [2 0 2]x0 + [2] [0 1 0] [0], [0 0 1] [3 1 2] [a](x0, x1) = [0 1 0]x0 + [3 1 3]x1 [1 0 0] [0 1 1] , [0] [0] = [0] [0] orientation: c#(a(c(c(y)),x)) = [6 2 4]x + [4 0 4]y + [4] >= [2 2 2]x = c#(c(c(a(x,0())))) c#(a(c(c(y)),x)) = [6 2 4]x + [4 0 4]y + [4] >= [0 0 2]x = c#(a(x,0())) c#(a(c(c(y)),x)) = [6 2 4]x + [4 0 4]y + [4] >= [2 0 2]x = c#(c(a(x,0()))) a(a(y,0()),0()) = y >= y = y [1 1 1] [0] c(c(y)) = [2 2 2]y + [2] >= y = y [2 0 2] [2] [3 2 3] [3 1 3] [2] [2 2 2] [3 1 2] [2] c(a(c(c(y)),x)) = [6 4 6]x + [6 2 6]y + [6] >= [6 2 6]x + [3 1 3]y + [6] = a(c(c(c(a(x,0())))),y) [3 1 3] [2 2 2] [2] [3 1 3] [0 1 1] [2] problem: DPs: TRS: a(a(y,0()),0()) -> y c(c(y)) -> y c(a(c(c(y)),x)) -> a(c(c(c(a(x,0())))),y) Qed