Term Rewriting System R: [a, x, k, d] f(a, empty) -> g(a, empty) f(a, cons(x, k)) -> f(cons(x, a), k) g(empty, d) -> d g(cons(x, k), d) -> g(k, cons(x, d)) Termination of R to be shown. Removing the following rules from R which fullfill a polynomial ordering: f(a, empty) -> g(a, empty) where the Polynomial interpretation: POL(g(x_1, x_2)) = x_1 + x_2 POL(f(x_1, x_2)) = 1 + x_1 + x_2 POL(empty) = 0 POL(cons(x_1, x_2)) = x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: f(a, cons(x, k)) -> f(cons(x, a), k) g(empty, d) -> d where the Polynomial interpretation: POL(g(x_1, x_2)) = 2 + x_1 + x_2 POL(f(x_1, x_2)) = 2 + x_1 + 2*x_2 POL(empty) = 2 POL(cons(x_1, x_2)) = 1 + x_1 + x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: g(cons(x, k), d) -> g(k, cons(x, d)) where the Polynomial interpretation: POL(g(x_1, x_2)) = 2 + 2*x_1 + x_2 POL(cons(x_1, x_2)) = 1 + x_1 + x_2 was used. All Rules of R can be deleted. Termination of R successfully shown. Duration: 0.400 seconds.