YES Problem: f(x,f(a(),a())) -> f(f(f(a(),a()),a()),f(a(),x)) Proof: DP Processor: DPs: f#(x,f(a(),a())) -> f#(a(),x) f#(x,f(a(),a())) -> f#(f(a(),a()),a()) f#(x,f(a(),a())) -> f#(f(f(a(),a()),a()),f(a(),x)) TRS: f(x,f(a(),a())) -> f(f(f(a(),a()),a()),f(a(),x)) EDG Processor: DPs: f#(x,f(a(),a())) -> f#(a(),x) f#(x,f(a(),a())) -> f#(f(a(),a()),a()) f#(x,f(a(),a())) -> f#(f(f(a(),a()),a()),f(a(),x)) TRS: f(x,f(a(),a())) -> f(f(f(a(),a()),a()),f(a(),x)) graph: f#(x,f(a(),a())) -> f#(f(f(a(),a()),a()),f(a(),x)) -> f#(x,f(a(),a())) -> f#(a(),x) f#(x,f(a(),a())) -> f#(f(f(a(),a()),a()),f(a(),x)) -> f#(x,f(a(),a())) -> f#(f(a(),a()),a()) f#(x,f(a(),a())) -> f#(f(f(a(),a()),a()),f(a(),x)) -> f#(x,f(a(),a())) -> f#(f(f(a(),a()),a()),f(a(),x)) f#(x,f(a(),a())) -> f#(a(),x) -> f#(x,f(a(),a())) -> f#(a(),x) f#(x,f(a(),a())) -> f#(a(),x) -> f#(x,f(a(),a())) -> f#(f(a(),a()),a()) f#(x,f(a(),a())) -> f#(a(),x) -> f#(x,f(a(),a())) -> f#(f(f(a(),a()),a()),f(a(),x)) CDG Processor: DPs: f#(x,f(a(),a())) -> f#(a(),x) f#(x,f(a(),a())) -> f#(f(a(),a()),a()) f#(x,f(a(),a())) -> f#(f(f(a(),a()),a()),f(a(),x)) TRS: f(x,f(a(),a())) -> f(f(f(a(),a()),a()),f(a(),x)) graph: f#(x,f(a(),a())) -> f#(a(),x) -> f#(x,f(a(),a())) -> f#(f(f(a(),a()),a()),f(a(),x)) f#(x,f(a(),a())) -> f#(a(),x) -> f#(x,f(a(),a())) -> f#(f(a(),a()),a()) f#(x,f(a(),a())) -> f#(a(),x) -> f#(x,f(a(),a())) -> f#(a(),x) SCC Processor: #sccs: 1 #rules: 1 #arcs: 3/9 DPs: f#(x,f(a(),a())) -> f#(a(),x) TRS: f(x,f(a(),a())) -> f(f(f(a(),a()),a()),f(a(),x)) Matrix Interpretation Processor: dim=2 interpretation: [f#](x0, x1) = [2 0]x0 + [1 0]x1, [0 1] [f](x0, x1) = [0 0]x0, [0] [a] = [2] orientation: f#(x,f(a(),a())) = [2 0]x + [2] >= [1 0]x = f#(a(),x) [0 1] [0] f(x,f(a(),a())) = [0 0]x >= [0] = f(f(f(a(),a()),a()),f(a(),x)) problem: DPs: TRS: f(x,f(a(),a())) -> f(f(f(a(),a()),a()),f(a(),x)) Qed