MAYBE Problem: f(x,c(x),c(y)) -> f(y,y,f(y,x,y)) f(s(x),y,z) -> f(x,s(c(y)),c(z)) f(c(x),x,y) -> c(y) g(x,y) -> x g(x,y) -> y Proof: DP Processor: DPs: f#(x,c(x),c(y)) -> f#(y,x,y) f#(x,c(x),c(y)) -> f#(y,y,f(y,x,y)) f#(s(x),y,z) -> f#(x,s(c(y)),c(z)) TRS: f(x,c(x),c(y)) -> f(y,y,f(y,x,y)) f(s(x),y,z) -> f(x,s(c(y)),c(z)) f(c(x),x,y) -> c(y) g(x,y) -> x g(x,y) -> y Usable Rule Processor: DPs: f#(x,c(x),c(y)) -> f#(y,x,y) f#(x,c(x),c(y)) -> f#(y,y,f(y,x,y)) f#(s(x),y,z) -> f#(x,s(c(y)),c(z)) TRS: f(x,c(x),c(y)) -> f(y,y,f(y,x,y)) f(s(x),y,z) -> f(x,s(c(y)),c(z)) f(c(x),x,y) -> c(y) EDG Processor: DPs: f#(x,c(x),c(y)) -> f#(y,x,y) f#(x,c(x),c(y)) -> f#(y,y,f(y,x,y)) f#(s(x),y,z) -> f#(x,s(c(y)),c(z)) TRS: f(x,c(x),c(y)) -> f(y,y,f(y,x,y)) f(s(x),y,z) -> f(x,s(c(y)),c(z)) f(c(x),x,y) -> c(y) graph: f#(s(x),y,z) -> f#(x,s(c(y)),c(z)) -> f#(s(x),y,z) -> f#(x,s(c(y)),c(z)) f#(x,c(x),c(y)) -> f#(y,y,f(y,x,y)) -> f#(s(x),y,z) -> f#(x,s(c(y)),c(z)) f#(x,c(x),c(y)) -> f#(y,x,y) -> f#(x,c(x),c(y)) -> f#(y,x,y) f#(x,c(x),c(y)) -> f#(y,x,y) -> f#(x,c(x),c(y)) -> f#(y,y,f(y,x,y)) f#(x,c(x),c(y)) -> f#(y,x,y) -> f#(s(x),y,z) -> f#(x,s(c(y)),c(z)) Restore Modifier: DPs: f#(x,c(x),c(y)) -> f#(y,x,y) f#(x,c(x),c(y)) -> f#(y,y,f(y,x,y)) f#(s(x),y,z) -> f#(x,s(c(y)),c(z)) TRS: f(x,c(x),c(y)) -> f(y,y,f(y,x,y)) f(s(x),y,z) -> f(x,s(c(y)),c(z)) f(c(x),x,y) -> c(y) g(x,y) -> x g(x,y) -> y SCC Processor: #sccs: 2 #rules: 2 #arcs: 5/9 DPs: f#(x,c(x),c(y)) -> f#(y,x,y) TRS: f(x,c(x),c(y)) -> f(y,y,f(y,x,y)) f(s(x),y,z) -> f(x,s(c(y)),c(z)) f(c(x),x,y) -> c(y) g(x,y) -> x g(x,y) -> y Open DPs: f#(s(x),y,z) -> f#(x,s(c(y)),c(z)) TRS: f(x,c(x),c(y)) -> f(y,y,f(y,x,y)) f(s(x),y,z) -> f(x,s(c(y)),c(z)) f(c(x),x,y) -> c(y) g(x,y) -> x g(x,y) -> y Matrix Interpretation Processor: dimension: 1 interpretation: [f#](x0, x1, x2) = x0, [g](x0, x1) = x0 + x1, [s](x0) = x0 + 1, [f](x0, x1, x2) = 0, [c](x0) = 0 orientation: f#(s(x),y,z) = x + 1 >= x = f#(x,s(c(y)),c(z)) f(x,c(x),c(y)) = 0 >= 0 = f(y,y,f(y,x,y)) f(s(x),y,z) = 0 >= 0 = f(x,s(c(y)),c(z)) f(c(x),x,y) = 0 >= 0 = c(y) g(x,y) = x + y >= x = x g(x,y) = x + y >= y = y problem: DPs: TRS: f(x,c(x),c(y)) -> f(y,y,f(y,x,y)) f(s(x),y,z) -> f(x,s(c(y)),c(z)) f(c(x),x,y) -> c(y) g(x,y) -> x g(x,y) -> y Qed