Term Rewriting System R: [ls, a, x, k] rev(ls) -> r1(ls, empty) r1(empty, a) -> a r1(cons(x, k), a) -> r1(k, cons(x, a)) Termination of R to be shown. Removing the following rules from R which fullfill a polynomial ordering: rev(ls) -> r1(ls, empty) where the Polynomial interpretation: POL(r1(x_1, x_2)) = x_1 + x_2 POL(rev(x_1)) = 1 + x_1 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: r1(empty, a) -> a where the Polynomial interpretation: POL(r1(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: r1(cons(x, k), a) -> r1(k, cons(x, a)) where the Polynomial interpretation: POL(r1(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: 0.387 seconds.