YES Problem: f(f(a(),x),a()) -> f(f(x,f(a(),a())),a()) Proof: DP Processor: DPs: f#(f(a(),x),a()) -> f#(a(),a()) f#(f(a(),x),a()) -> f#(x,f(a(),a())) f#(f(a(),x),a()) -> f#(f(x,f(a(),a())),a()) TRS: f(f(a(),x),a()) -> f(f(x,f(a(),a())),a()) EDG Processor: DPs: f#(f(a(),x),a()) -> f#(a(),a()) f#(f(a(),x),a()) -> f#(x,f(a(),a())) f#(f(a(),x),a()) -> f#(f(x,f(a(),a())),a()) TRS: f(f(a(),x),a()) -> f(f(x,f(a(),a())),a()) graph: f#(f(a(),x),a()) -> f#(f(x,f(a(),a())),a()) -> f#(f(a(),x),a()) -> f#(a(),a()) f#(f(a(),x),a()) -> f#(f(x,f(a(),a())),a()) -> f#(f(a(),x),a()) -> f#(x,f(a(),a())) f#(f(a(),x),a()) -> f#(f(x,f(a(),a())),a()) -> f#(f(a(),x),a()) -> f#(f(x,f(a(),a())),a()) CDG Processor: DPs: f#(f(a(),x),a()) -> f#(a(),a()) f#(f(a(),x),a()) -> f#(x,f(a(),a())) f#(f(a(),x),a()) -> f#(f(x,f(a(),a())),a()) TRS: f(f(a(),x),a()) -> f(f(x,f(a(),a())),a()) graph: Qed