MAYBE We are left with following problem, upon which TcT provides the certificate MAYBE. Strict Trs: { #equal(@x, @y) -> #eq(@x, @y) , appendreverse(@toreverse, @sofar) -> appendreverse#1(@toreverse, @sofar) , appendreverse#1(::(@a, @as), @sofar) -> appendreverse(@as, ::(@a, @sofar)) , appendreverse#1(nil(), @sofar) -> @sofar , bfs(@queue, @futurequeue, @x) -> bfs#1(@queue, @futurequeue, @x) , bfs#1(::(@t, @ts), @futurequeue, @x) -> bfs#3(@t, @futurequeue, @ts, @x) , bfs#1(nil(), @futurequeue, @x) -> bfs#2(@futurequeue, @x) , bfs#3(leaf(), @futurequeue, @ts, @x) -> bfs(@ts, @futurequeue, @x) , bfs#3(node(@y, @t1, @t2), @futurequeue, @ts, @x) -> bfs#4(#equal(@x, @y), @futurequeue, @t1, @t2, @ts, @x, @y) , bfs#2(::(@t, @ts), @x) -> bfs(reverse(::(@t, @ts)), nil(), @x) , bfs#2(nil(), @x) -> leaf() , reverse(@xs) -> appendreverse(@xs, nil()) , bfs#4(#false(), @futurequeue, @t1, @t2, @ts, @x, @y) -> bfs(@ts, ::(@t2, ::(@t1, @futurequeue)), @x) , bfs#4(#true(), @futurequeue, @t1, @t2, @ts, @x, @y) -> node(@y, @t1, @t2) , bfs2(@t, @x) -> bfs2#1(dobfs(@t, @x), @x) , dobfs(@t, @x) -> bfs(::(@t, nil()), nil(), @x) , bfs2#1(@t', @x) -> dobfs(@t', @x) , dfs(@queue, @x) -> dfs#1(@queue, @x) , dfs#1(::(@t, @ts), @x) -> dfs#2(@t, @t, @ts, @x) , dfs#1(nil(), @x) -> leaf() , dfs#2(leaf(), @t, @ts, @x) -> dfs(@ts, @x) , dfs#2(node(@a, @t1, @t2), @t, @ts, @x) -> dfs#3(#equal(@a, @x), @t, @t1, @t2, @ts, @x) , dfs#3(#false(), @t, @t1, @t2, @ts, @x) -> dfs(::(@t1, ::(@t2, @ts)), @x) , dfs#3(#true(), @t, @t1, @t2, @ts, @x) -> @t , dodfs(@t, @x) -> dfs(::(@t, nil()), @x) } Weak Trs: { #eq(::(@x_1, @x_2), ::(@y_1, @y_2)) -> #and(#eq(@x_1, @y_1), #eq(@x_2, @y_2)) , #eq(::(@x_1, @x_2), nil()) -> #false() , #eq(::(@x_1, @x_2), leaf()) -> #false() , #eq(::(@x_1, @x_2), node(@y_1, @y_2, @y_3)) -> #false() , #eq(nil(), ::(@y_1, @y_2)) -> #false() , #eq(nil(), nil()) -> #true() , #eq(nil(), leaf()) -> #false() , #eq(nil(), node(@y_1, @y_2, @y_3)) -> #false() , #eq(leaf(), ::(@y_1, @y_2)) -> #false() , #eq(leaf(), nil()) -> #false() , #eq(leaf(), leaf()) -> #true() , #eq(leaf(), node(@y_1, @y_2, @y_3)) -> #false() , #eq(node(@x_1, @x_2, @x_3), ::(@y_1, @y_2)) -> #false() , #eq(node(@x_1, @x_2, @x_3), nil()) -> #false() , #eq(node(@x_1, @x_2, @x_3), leaf()) -> #false() , #eq(node(@x_1, @x_2, @x_3), node(@y_1, @y_2, @y_3)) -> #and(#eq(@x_1, @y_1), #and(#eq(@x_2, @y_2), #eq(@x_3, @y_3))) , #eq(#0(), #0()) -> #true() , #eq(#0(), #neg(@y)) -> #false() , #eq(#0(), #pos(@y)) -> #false() , #eq(#0(), #s(@y)) -> #false() , #eq(#neg(@x), #0()) -> #false() , #eq(#neg(@x), #neg(@y)) -> #eq(@x, @y) , #eq(#neg(@x), #pos(@y)) -> #false() , #eq(#pos(@x), #0()) -> #false() , #eq(#pos(@x), #neg(@y)) -> #false() , #eq(#pos(@x), #pos(@y)) -> #eq(@x, @y) , #eq(#s(@x), #0()) -> #false() , #eq(#s(@x), #s(@y)) -> #eq(@x, @y) , #and(#false(), #false()) -> #false() , #and(#false(), #true()) -> #false() , #and(#true(), #false()) -> #false() , #and(#true(), #true()) -> #true() } Obligation: innermost runtime complexity Answer: MAYBE None of the processors succeeded. Details of failed attempt(s): ----------------------------- 1) 'Fastest' failed due to the following reason: None of the processors succeeded. Details of failed attempt(s): ----------------------------- 1) 'custom shape polynomial interpretation' failed due to the following reason: The input cannot be shown compatible 2) 'custom shape polynomial interpretation' failed due to the following reason: The input cannot be shown compatible 3) 'linear polynomial interpretation' failed due to the following reason: The input cannot be shown compatible 2) 'Fastest' failed due to the following reason: None of the processors succeeded. Details of failed attempt(s): ----------------------------- 1) 'matrix interpretation of dimension 4' failed due to the following reason: Following exception was raised: stack overflow 2) 'matrix interpretation of dimension 3' failed due to the following reason: The input cannot be shown compatible 3) 'matrix interpretation of dimension 3' failed due to the following reason: The input cannot be shown compatible 4) 'matrix interpretation of dimension 2' failed due to the following reason: The input cannot be shown compatible 5) 'matrix interpretation of dimension 2' failed due to the following reason: The input cannot be shown compatible 6) 'matrix interpretation of dimension 1' failed due to the following reason: The input cannot be shown compatible Arrrr..