YES Problem: p(f(f(x))) -> q(f(g(x))) p(g(g(x))) -> q(g(f(x))) q(f(f(x))) -> p(f(g(x))) q(g(g(x))) -> p(g(f(x))) Proof: DP Processor: DPs: p#(f(f(x))) -> q#(f(g(x))) p#(g(g(x))) -> q#(g(f(x))) q#(f(f(x))) -> p#(f(g(x))) q#(g(g(x))) -> p#(g(f(x))) TRS: p(f(f(x))) -> q(f(g(x))) p(g(g(x))) -> q(g(f(x))) q(f(f(x))) -> p(f(g(x))) q(g(g(x))) -> p(g(f(x))) Usable Rule Processor: DPs: p#(f(f(x))) -> q#(f(g(x))) p#(g(g(x))) -> q#(g(f(x))) q#(f(f(x))) -> p#(f(g(x))) q#(g(g(x))) -> p#(g(f(x))) TRS: Arctic Interpretation Processor: dimension: 2 usable rules: interpretation: [q#](x0) = [0 0]x0 + [0], [p#](x0) = [0 0]x0 + [0], [2 0 ] [2] [g](x0) = [-& 0 ]x0 + [1], [-& -&] [1] [f](x0) = [-& 1 ]x0 + [2] orientation: p#(f(f(x))) = [-& 2 ]x + [3] >= [-& 1 ]x + [2] = q#(f(g(x))) p#(g(g(x))) = [4 2]x + [4] >= [-& 1 ]x + [3] = q#(g(f(x))) q#(f(f(x))) = [-& 2 ]x + [3] >= [-& 1 ]x + [2] = p#(f(g(x))) q#(g(g(x))) = [4 2]x + [4] >= [-& 1 ]x + [3] = p#(g(f(x))) problem: DPs: TRS: Qed