Problem CiME 04 append-wrong

Tool CaT

Execution TimeUnknown
Answer
MAYBE
InputCiME 04 append-wrong

stdout:

MAYBE

Problem:
 is_empty(nil()) -> true()
 is_empty(cons(x,l)) -> false()
 hd(cons(x,l)) -> x
 tl(cons(x,l)) -> cons(x,l)
 append(l1,l2) -> ifappend(l1,l2,is_empty(l1))
 ifappend(l1,l2,true()) -> l2
 ifappend(l1,l2,false()) -> cons(hd(l1),append(tl(l1),l2))

Proof:
 Open

Tool IRC1

Execution TimeUnknown
Answer
MAYBE
InputCiME 04 append-wrong

stdout:

MAYBE

Tool IRC2

Execution TimeUnknown
Answer
TIMEOUT
InputCiME 04 append-wrong

stdout:

TIMEOUT

'Fastest (timeout of 60.0 seconds)'
-----------------------------------
Answer:           TIMEOUT
Input Problem:    innermost runtime-complexity with respect to
  Rules:
    {  is_empty(nil()) -> true()
     , is_empty(cons(x, l)) -> false()
     , hd(cons(x, l)) -> x
     , tl(cons(x, l)) -> cons(x, l)
     , append(l1, l2) -> ifappend(l1, l2, is_empty(l1))
     , ifappend(l1, l2, true()) -> l2
     , ifappend(l1, l2, false()) -> cons(hd(l1), append(tl(l1), l2))}

Proof Output:    
  Computation stopped due to timeout after 60.0 seconds

Tool RC1

Execution TimeUnknown
Answer
MAYBE
InputCiME 04 append-wrong

stdout:

MAYBE

Tool RC2

Execution TimeUnknown
Answer
MAYBE
InputCiME 04 append-wrong

stdout:

MAYBE

'Fastest (timeout of 60.0 seconds)'
-----------------------------------
Answer:           MAYBE
Input Problem:    runtime-complexity with respect to
  Rules:
    {  is_empty(nil()) -> true()
     , is_empty(cons(x, l)) -> false()
     , hd(cons(x, l)) -> x
     , tl(cons(x, l)) -> cons(x, l)
     , append(l1, l2) -> ifappend(l1, l2, is_empty(l1))
     , ifappend(l1, l2, true()) -> l2
     , ifappend(l1, l2, false()) -> cons(hd(l1), append(tl(l1), l2))}

Proof Output:    
  None of the processors succeeded.
  
  Details of failed attempt(s):
  -----------------------------
    1) 'wdg' failed due to the following reason:
         Transformation Details:
         -----------------------
           We have computed the following set of weak (innermost) dependency pairs:
           
             {  1: is_empty^#(nil()) -> c_0()
              , 2: is_empty^#(cons(x, l)) -> c_1()
              , 3: hd^#(cons(x, l)) -> c_2(x)
              , 4: tl^#(cons(x, l)) -> c_3(x, l)
              , 5: append^#(l1, l2) -> c_4(ifappend^#(l1, l2, is_empty(l1)))
              , 6: ifappend^#(l1, l2, true()) -> c_5(l2)
              , 7: ifappend^#(l1, l2, false()) ->
                   c_6(hd^#(l1), append^#(tl(l1), l2))}
           
           Following Dependency Graph (modulo SCCs) was computed. (Answers to
           subproofs are indicated to the right.)
           
             ->{5,7}                                                     [       MAYBE        ]
                |
                |->{3}                                                   [         NA         ]
                |
                `->{6}                                                   [         NA         ]
             
             ->{4}                                                       [   YES(?,O(n^3))    ]
             
             ->{2}                                                       [    YES(?,O(1))     ]
             
             ->{1}                                                       [    YES(?,O(1))     ]
             
           
         
         Sub-problems:
         -------------
           * Path {1}: YES(?,O(1))
             ---------------------
             
             The usable rules of this path are empty.
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {},
                 Uargs(c_4) = {}, Uargs(ifappend^#) = {}, Uargs(c_5) = {},
                 Uargs(c_6) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [0 0 0] x1 + [0]
                               [0 0 0]      [0]
                               [0 0 0]      [0]
                nil() = [0]
                        [0]
                        [0]
                true() = [0]
                         [0]
                         [0]
                cons(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                               [0 0 0]      [0 0 0]      [0]
                               [0 0 0]      [0 0 0]      [0]
                false() = [0]
                          [0]
                          [0]
                hd(x1) = [0 0 0] x1 + [0]
                         [0 0 0]      [0]
                         [0 0 0]      [0]
                tl(x1) = [0 0 0] x1 + [0]
                         [0 0 0]      [0]
                         [0 0 0]      [0]
                append(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                                 [0 0 0]      [0 0 0]      [0]
                                 [0 0 0]      [0 0 0]      [0]
                ifappend(x1, x2, x3) = [0 0 0] x1 + [0 0 0] x2 + [0 0 0] x3 + [0]
                                       [0 0 0]      [0 0 0]      [0 0 0]      [0]
                                       [0 0 0]      [0 0 0]      [0 0 0]      [0]
                is_empty^#(x1) = [0 0 0] x1 + [0]
                                 [0 0 0]      [0]
                                 [0 0 0]      [0]
                c_0() = [0]
                        [0]
                        [0]
                c_1() = [0]
                        [0]
                        [0]
                hd^#(x1) = [0 0 0] x1 + [0]
                           [0 0 0]      [0]
                           [0 0 0]      [0]
                c_2(x1) = [0 0 0] x1 + [0]
                          [0 0 0]      [0]
                          [0 0 0]      [0]
                tl^#(x1) = [0 0 0] x1 + [0]
                           [0 0 0]      [0]
                           [0 0 0]      [0]
                c_3(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                              [0 0 0]      [0 0 0]      [0]
                              [0 0 0]      [0 0 0]      [0]
                append^#(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                                   [0 0 0]      [0 0 0]      [0]
                                   [0 0 0]      [0 0 0]      [0]
                c_4(x1) = [0 0 0] x1 + [0]
                          [0 0 0]      [0]
                          [0 0 0]      [0]
                ifappend^#(x1, x2, x3) = [0 0 0] x1 + [0 0 0] x2 + [0 0 0] x3 + [0]
                                         [0 0 0]      [0 0 0]      [0 0 0]      [0]
                                         [0 0 0]      [0 0 0]      [0 0 0]      [0]
                c_5(x1) = [0 0 0] x1 + [0]
                          [0 0 0]      [0]
                          [0 0 0]      [0]
                c_6(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                              [0 0 0]      [0 0 0]      [0]
                              [0 0 0]      [0 0 0]      [0]
             
             We apply the sub-processor on the resulting sub-problem:
             
             'matrix-interpretation of dimension 3'
             --------------------------------------
             Answer:           YES(?,O(1))
             Input Problem:    DP runtime-complexity with respect to
               Strict Rules: {is_empty^#(nil()) -> c_0()}
               Weak Rules: {}
             
             Proof Output:    
               The following argument positions are usable:
                 Uargs(is_empty^#) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                nil() = [2]
                        [2]
                        [2]
                is_empty^#(x1) = [0 2 0] x1 + [7]
                                 [2 2 0]      [3]
                                 [2 2 2]      [3]
                c_0() = [0]
                        [1]
                        [1]
           
           * Path {2}: YES(?,O(1))
             ---------------------
             
             The usable rules of this path are empty.
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {},
                 Uargs(c_4) = {}, Uargs(ifappend^#) = {}, Uargs(c_5) = {},
                 Uargs(c_6) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [0 0 0] x1 + [0]
                               [0 0 0]      [0]
                               [0 0 0]      [0]
                nil() = [0]
                        [0]
                        [0]
                true() = [0]
                         [0]
                         [0]
                cons(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                               [0 0 0]      [0 0 0]      [0]
                               [0 0 0]      [0 0 0]      [0]
                false() = [0]
                          [0]
                          [0]
                hd(x1) = [0 0 0] x1 + [0]
                         [0 0 0]      [0]
                         [0 0 0]      [0]
                tl(x1) = [0 0 0] x1 + [0]
                         [0 0 0]      [0]
                         [0 0 0]      [0]
                append(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                                 [0 0 0]      [0 0 0]      [0]
                                 [0 0 0]      [0 0 0]      [0]
                ifappend(x1, x2, x3) = [0 0 0] x1 + [0 0 0] x2 + [0 0 0] x3 + [0]
                                       [0 0 0]      [0 0 0]      [0 0 0]      [0]
                                       [0 0 0]      [0 0 0]      [0 0 0]      [0]
                is_empty^#(x1) = [0 0 0] x1 + [0]
                                 [0 0 0]      [0]
                                 [0 0 0]      [0]
                c_0() = [0]
                        [0]
                        [0]
                c_1() = [0]
                        [0]
                        [0]
                hd^#(x1) = [0 0 0] x1 + [0]
                           [0 0 0]      [0]
                           [0 0 0]      [0]
                c_2(x1) = [0 0 0] x1 + [0]
                          [0 0 0]      [0]
                          [0 0 0]      [0]
                tl^#(x1) = [0 0 0] x1 + [0]
                           [0 0 0]      [0]
                           [0 0 0]      [0]
                c_3(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                              [0 0 0]      [0 0 0]      [0]
                              [0 0 0]      [0 0 0]      [0]
                append^#(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                                   [0 0 0]      [0 0 0]      [0]
                                   [0 0 0]      [0 0 0]      [0]
                c_4(x1) = [0 0 0] x1 + [0]
                          [0 0 0]      [0]
                          [0 0 0]      [0]
                ifappend^#(x1, x2, x3) = [0 0 0] x1 + [0 0 0] x2 + [0 0 0] x3 + [0]
                                         [0 0 0]      [0 0 0]      [0 0 0]      [0]
                                         [0 0 0]      [0 0 0]      [0 0 0]      [0]
                c_5(x1) = [0 0 0] x1 + [0]
                          [0 0 0]      [0]
                          [0 0 0]      [0]
                c_6(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                              [0 0 0]      [0 0 0]      [0]
                              [0 0 0]      [0 0 0]      [0]
             
             We apply the sub-processor on the resulting sub-problem:
             
             'matrix-interpretation of dimension 3'
             --------------------------------------
             Answer:           YES(?,O(1))
             Input Problem:    DP runtime-complexity with respect to
               Strict Rules: {is_empty^#(cons(x, l)) -> c_1()}
               Weak Rules: {}
             
             Proof Output:    
               The following argument positions are usable:
                 Uargs(cons) = {}, Uargs(is_empty^#) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                cons(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [2]
                               [0 0 0]      [0 0 0]      [2]
                               [0 0 0]      [0 0 0]      [2]
                is_empty^#(x1) = [0 2 0] x1 + [7]
                                 [2 2 0]      [3]
                                 [2 2 2]      [3]
                c_1() = [0]
                        [1]
                        [1]
           
           * Path {4}: YES(?,O(n^3))
             -----------------------
             
             The usable rules of this path are empty.
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {},
                 Uargs(c_4) = {}, Uargs(ifappend^#) = {}, Uargs(c_5) = {},
                 Uargs(c_6) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [0 0 0] x1 + [0]
                               [0 0 0]      [0]
                               [0 0 0]      [0]
                nil() = [0]
                        [0]
                        [0]
                true() = [0]
                         [0]
                         [0]
                cons(x1, x2) = [1 3 3] x1 + [1 3 3] x2 + [0]
                               [0 1 1]      [0 1 1]      [0]
                               [0 0 1]      [0 0 1]      [0]
                false() = [0]
                          [0]
                          [0]
                hd(x1) = [0 0 0] x1 + [0]
                         [0 0 0]      [0]
                         [0 0 0]      [0]
                tl(x1) = [0 0 0] x1 + [0]
                         [0 0 0]      [0]
                         [0 0 0]      [0]
                append(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                                 [0 0 0]      [0 0 0]      [0]
                                 [0 0 0]      [0 0 0]      [0]
                ifappend(x1, x2, x3) = [0 0 0] x1 + [0 0 0] x2 + [0 0 0] x3 + [0]
                                       [0 0 0]      [0 0 0]      [0 0 0]      [0]
                                       [0 0 0]      [0 0 0]      [0 0 0]      [0]
                is_empty^#(x1) = [0 0 0] x1 + [0]
                                 [0 0 0]      [0]
                                 [0 0 0]      [0]
                c_0() = [0]
                        [0]
                        [0]
                c_1() = [0]
                        [0]
                        [0]
                hd^#(x1) = [0 0 0] x1 + [0]
                           [0 0 0]      [0]
                           [0 0 0]      [0]
                c_2(x1) = [0 0 0] x1 + [0]
                          [0 0 0]      [0]
                          [0 0 0]      [0]
                tl^#(x1) = [1 3 3] x1 + [0]
                           [0 0 0]      [0]
                           [0 0 0]      [0]
                c_3(x1, x2) = [1 0 1] x1 + [1 0 1] x2 + [0]
                              [0 0 0]      [0 0 0]      [0]
                              [0 0 0]      [0 0 0]      [0]
                append^#(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                                   [0 0 0]      [0 0 0]      [0]
                                   [0 0 0]      [0 0 0]      [0]
                c_4(x1) = [0 0 0] x1 + [0]
                          [0 0 0]      [0]
                          [0 0 0]      [0]
                ifappend^#(x1, x2, x3) = [0 0 0] x1 + [0 0 0] x2 + [0 0 0] x3 + [0]
                                         [0 0 0]      [0 0 0]      [0 0 0]      [0]
                                         [0 0 0]      [0 0 0]      [0 0 0]      [0]
                c_5(x1) = [0 0 0] x1 + [0]
                          [0 0 0]      [0]
                          [0 0 0]      [0]
                c_6(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                              [0 0 0]      [0 0 0]      [0]
                              [0 0 0]      [0 0 0]      [0]
             
             We apply the sub-processor on the resulting sub-problem:
             
             'matrix-interpretation of dimension 3'
             --------------------------------------
             Answer:           YES(?,O(n^1))
             Input Problem:    DP runtime-complexity with respect to
               Strict Rules: {tl^#(cons(x, l)) -> c_3(x, l)}
               Weak Rules: {}
             
             Proof Output:    
               The following argument positions are usable:
                 Uargs(cons) = {}, Uargs(tl^#) = {}, Uargs(c_3) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                cons(x1, x2) = [1 2 2] x1 + [1 7 2] x2 + [2]
                               [0 0 2]      [0 0 2]      [2]
                               [0 0 0]      [0 0 0]      [2]
                tl^#(x1) = [2 2 2] x1 + [3]
                           [2 2 0]      [7]
                           [2 2 0]      [7]
                c_3(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                              [0 0 0]      [0 0 0]      [1]
                              [0 0 0]      [0 0 0]      [1]
           
           * Path {5,7}: MAYBE
             -----------------
             
             The usable rules for this path are:
             
               {  is_empty(nil()) -> true()
                , is_empty(cons(x, l)) -> false()
                , tl(cons(x, l)) -> cons(x, l)}
             
             The weight gap principle does not apply:
               The input cannot be shown compatible
             Complexity induced by the adequate RMI: MAYBE
             
             We apply the sub-processor on the resulting sub-problem:
             
             'matrix-interpretation of dimension 3'
             --------------------------------------
             Answer:           MAYBE
             Input Problem:    runtime-complexity with respect to
               Rules:
                 {  append^#(l1, l2) -> c_4(ifappend^#(l1, l2, is_empty(l1)))
                  , ifappend^#(l1, l2, false()) ->
                    c_6(hd^#(l1), append^#(tl(l1), l2))
                  , is_empty(nil()) -> true()
                  , is_empty(cons(x, l)) -> false()
                  , tl(cons(x, l)) -> cons(x, l)}
             
             Proof Output:    
               The input cannot be shown compatible
           
           * Path {5,7}->{3}: NA
             -------------------
             
             The usable rules for this path are:
             
               {  is_empty(nil()) -> true()
                , is_empty(cons(x, l)) -> false()
                , tl(cons(x, l)) -> cons(x, l)}
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {1}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {1}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {1}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {1},
                 Uargs(c_4) = {1}, Uargs(ifappend^#) = {1, 3}, Uargs(c_5) = {},
                 Uargs(c_6) = {1, 2}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [2 0 0] x1 + [2]
                               [0 0 0]      [3]
                               [0 0 0]      [3]
                nil() = [0]
                        [0]
                        [0]
                true() = [1]
                         [1]
                         [1]
                cons(x1, x2) = [1 0 0] x1 + [1 0 0] x2 + [0]
                               [0 0 0]      [0 0 0]      [0]
                               [0 0 0]      [0 0 0]      [0]
                false() = [1]
                          [1]
                          [1]
                hd(x1) = [0 0 0] x1 + [0]
                         [0 0 0]      [0]
                         [0 0 0]      [0]
                tl(x1) = [2 0 0] x1 + [3]
                         [0 0 0]      [3]
                         [0 0 0]      [3]
                append(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                                 [0 0 0]      [0 0 0]      [0]
                                 [0 0 0]      [0 0 0]      [0]
                ifappend(x1, x2, x3) = [0 0 0] x1 + [0 0 0] x2 + [0 0 0] x3 + [0]
                                       [0 0 0]      [0 0 0]      [0 0 0]      [0]
                                       [0 0 0]      [0 0 0]      [0 0 0]      [0]
                is_empty^#(x1) = [0 0 0] x1 + [0]
                                 [0 0 0]      [0]
                                 [0 0 0]      [0]
                c_0() = [0]
                        [0]
                        [0]
                c_1() = [0]
                        [0]
                        [0]
                hd^#(x1) = [3 3 3] x1 + [0]
                           [0 0 0]      [0]
                           [0 0 0]      [0]
                c_2(x1) = [1 0 0] x1 + [0]
                          [0 0 0]      [0]
                          [0 0 0]      [0]
                tl^#(x1) = [0 0 0] x1 + [0]
                           [0 0 0]      [0]
                           [0 0 0]      [0]
                c_3(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                              [0 0 0]      [0 0 0]      [0]
                              [0 0 0]      [0 0 0]      [0]
                append^#(x1, x2) = [3 0 0] x1 + [0 0 0] x2 + [0]
                                   [0 0 0]      [0 0 0]      [0]
                                   [0 0 0]      [0 0 0]      [0]
                c_4(x1) = [1 0 0] x1 + [0]
                          [0 1 0]      [0]
                          [0 0 1]      [0]
                ifappend^#(x1, x2, x3) = [3 0 0] x1 + [0 0 0] x2 + [3 0 0] x3 + [0]
                                         [0 0 0]      [0 0 0]      [0 0 0]      [0]
                                         [0 0 0]      [0 0 0]      [0 0 0]      [0]
                c_5(x1) = [0 0 0] x1 + [0]
                          [0 0 0]      [0]
                          [0 0 0]      [0]
                c_6(x1, x2) = [1 0 0] x1 + [1 0 0] x2 + [0]
                              [0 1 0]      [0 1 0]      [0]
                              [0 0 1]      [0 0 1]      [0]
             Complexity induced by the adequate RMI: YES(?,O(n^1))
             
             We have not generated a proof for the resulting sub-problem.
           
           * Path {5,7}->{6}: NA
             -------------------
             
             The usable rules for this path are:
             
               {  is_empty(nil()) -> true()
                , is_empty(cons(x, l)) -> false()
                , tl(cons(x, l)) -> cons(x, l)}
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {1}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {1}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {1}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {1},
                 Uargs(c_4) = {1}, Uargs(ifappend^#) = {1, 3}, Uargs(c_5) = {},
                 Uargs(c_6) = {1, 2}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [2 0 0] x1 + [2]
                               [0 0 0]      [3]
                               [0 0 0]      [3]
                nil() = [0]
                        [0]
                        [0]
                true() = [1]
                         [1]
                         [1]
                cons(x1, x2) = [1 0 0] x1 + [1 0 0] x2 + [0]
                               [0 0 0]      [0 0 0]      [0]
                               [0 0 0]      [0 0 0]      [0]
                false() = [1]
                          [1]
                          [1]
                hd(x1) = [0 0 0] x1 + [0]
                         [0 0 0]      [0]
                         [0 0 0]      [0]
                tl(x1) = [2 0 0] x1 + [3]
                         [0 0 0]      [3]
                         [0 0 0]      [3]
                append(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                                 [0 0 0]      [0 0 0]      [0]
                                 [0 0 0]      [0 0 0]      [0]
                ifappend(x1, x2, x3) = [0 0 0] x1 + [0 0 0] x2 + [0 0 0] x3 + [0]
                                       [0 0 0]      [0 0 0]      [0 0 0]      [0]
                                       [0 0 0]      [0 0 0]      [0 0 0]      [0]
                is_empty^#(x1) = [0 0 0] x1 + [0]
                                 [0 0 0]      [0]
                                 [0 0 0]      [0]
                c_0() = [0]
                        [0]
                        [0]
                c_1() = [0]
                        [0]
                        [0]
                hd^#(x1) = [3 0 0] x1 + [0]
                           [0 0 0]      [0]
                           [0 0 0]      [0]
                c_2(x1) = [0 0 0] x1 + [0]
                          [0 0 0]      [0]
                          [0 0 0]      [0]
                tl^#(x1) = [0 0 0] x1 + [0]
                           [0 0 0]      [0]
                           [0 0 0]      [0]
                c_3(x1, x2) = [0 0 0] x1 + [0 0 0] x2 + [0]
                              [0 0 0]      [0 0 0]      [0]
                              [0 0 0]      [0 0 0]      [0]
                append^#(x1, x2) = [3 0 0] x1 + [0 0 0] x2 + [0]
                                   [0 0 0]      [0 0 0]      [0]
                                   [0 0 0]      [0 0 0]      [0]
                c_4(x1) = [1 0 0] x1 + [0]
                          [0 1 0]      [0]
                          [0 0 1]      [0]
                ifappend^#(x1, x2, x3) = [3 3 3] x1 + [0 0 0] x2 + [3 0 0] x3 + [0]
                                         [0 0 0]      [0 0 0]      [0 0 0]      [0]
                                         [0 0 0]      [0 0 0]      [0 0 0]      [0]
                c_5(x1) = [1 1 1] x1 + [0]
                          [0 0 0]      [0]
                          [0 0 0]      [0]
                c_6(x1, x2) = [1 0 0] x1 + [1 0 0] x2 + [0]
                              [0 1 0]      [0 1 0]      [0]
                              [0 0 1]      [0 0 1]      [0]
             Complexity induced by the adequate RMI: YES(?,O(n^1))
             
             We have not generated a proof for the resulting sub-problem.
    
    2) 'wdg' failed due to the following reason:
         Transformation Details:
         -----------------------
           We have computed the following set of weak (innermost) dependency pairs:
           
             {  1: is_empty^#(nil()) -> c_0()
              , 2: is_empty^#(cons(x, l)) -> c_1()
              , 3: hd^#(cons(x, l)) -> c_2(x)
              , 4: tl^#(cons(x, l)) -> c_3(x, l)
              , 5: append^#(l1, l2) -> c_4(ifappend^#(l1, l2, is_empty(l1)))
              , 6: ifappend^#(l1, l2, true()) -> c_5(l2)
              , 7: ifappend^#(l1, l2, false()) ->
                   c_6(hd^#(l1), append^#(tl(l1), l2))}
           
           Following Dependency Graph (modulo SCCs) was computed. (Answers to
           subproofs are indicated to the right.)
           
             ->{5,7}                                                     [       MAYBE        ]
                |
                |->{3}                                                   [         NA         ]
                |
                `->{6}                                                   [         NA         ]
             
             ->{4}                                                       [   YES(?,O(n^2))    ]
             
             ->{2}                                                       [    YES(?,O(1))     ]
             
             ->{1}                                                       [    YES(?,O(1))     ]
             
           
         
         Sub-problems:
         -------------
           * Path {1}: YES(?,O(1))
             ---------------------
             
             The usable rules of this path are empty.
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {},
                 Uargs(c_4) = {}, Uargs(ifappend^#) = {}, Uargs(c_5) = {},
                 Uargs(c_6) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [0 0] x1 + [0]
                               [0 0]      [0]
                nil() = [0]
                        [0]
                true() = [0]
                         [0]
                cons(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                               [0 0]      [0 0]      [0]
                false() = [0]
                          [0]
                hd(x1) = [0 0] x1 + [0]
                         [0 0]      [0]
                tl(x1) = [0 0] x1 + [0]
                         [0 0]      [0]
                append(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                                 [0 0]      [0 0]      [0]
                ifappend(x1, x2, x3) = [0 0] x1 + [0 0] x2 + [0 0] x3 + [0]
                                       [0 0]      [0 0]      [0 0]      [0]
                is_empty^#(x1) = [0 0] x1 + [0]
                                 [0 0]      [0]
                c_0() = [0]
                        [0]
                c_1() = [0]
                        [0]
                hd^#(x1) = [0 0] x1 + [0]
                           [0 0]      [0]
                c_2(x1) = [0 0] x1 + [0]
                          [0 0]      [0]
                tl^#(x1) = [0 0] x1 + [0]
                           [0 0]      [0]
                c_3(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                              [0 0]      [0 0]      [0]
                append^#(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                                   [0 0]      [0 0]      [0]
                c_4(x1) = [0 0] x1 + [0]
                          [0 0]      [0]
                ifappend^#(x1, x2, x3) = [0 0] x1 + [0 0] x2 + [0 0] x3 + [0]
                                         [0 0]      [0 0]      [0 0]      [0]
                c_5(x1) = [0 0] x1 + [0]
                          [0 0]      [0]
                c_6(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                              [0 0]      [0 0]      [0]
             
             We apply the sub-processor on the resulting sub-problem:
             
             'matrix-interpretation of dimension 2'
             --------------------------------------
             Answer:           YES(?,O(1))
             Input Problem:    DP runtime-complexity with respect to
               Strict Rules: {is_empty^#(nil()) -> c_0()}
               Weak Rules: {}
             
             Proof Output:    
               The following argument positions are usable:
                 Uargs(is_empty^#) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                nil() = [2]
                        [2]
                is_empty^#(x1) = [2 0] x1 + [7]
                                 [2 2]      [7]
                c_0() = [0]
                        [1]
           
           * Path {2}: YES(?,O(1))
             ---------------------
             
             The usable rules of this path are empty.
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {},
                 Uargs(c_4) = {}, Uargs(ifappend^#) = {}, Uargs(c_5) = {},
                 Uargs(c_6) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [0 0] x1 + [0]
                               [0 0]      [0]
                nil() = [0]
                        [0]
                true() = [0]
                         [0]
                cons(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                               [0 0]      [0 0]      [0]
                false() = [0]
                          [0]
                hd(x1) = [0 0] x1 + [0]
                         [0 0]      [0]
                tl(x1) = [0 0] x1 + [0]
                         [0 0]      [0]
                append(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                                 [0 0]      [0 0]      [0]
                ifappend(x1, x2, x3) = [0 0] x1 + [0 0] x2 + [0 0] x3 + [0]
                                       [0 0]      [0 0]      [0 0]      [0]
                is_empty^#(x1) = [0 0] x1 + [0]
                                 [0 0]      [0]
                c_0() = [0]
                        [0]
                c_1() = [0]
                        [0]
                hd^#(x1) = [0 0] x1 + [0]
                           [0 0]      [0]
                c_2(x1) = [0 0] x1 + [0]
                          [0 0]      [0]
                tl^#(x1) = [0 0] x1 + [0]
                           [0 0]      [0]
                c_3(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                              [0 0]      [0 0]      [0]
                append^#(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                                   [0 0]      [0 0]      [0]
                c_4(x1) = [0 0] x1 + [0]
                          [0 0]      [0]
                ifappend^#(x1, x2, x3) = [0 0] x1 + [0 0] x2 + [0 0] x3 + [0]
                                         [0 0]      [0 0]      [0 0]      [0]
                c_5(x1) = [0 0] x1 + [0]
                          [0 0]      [0]
                c_6(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                              [0 0]      [0 0]      [0]
             
             We apply the sub-processor on the resulting sub-problem:
             
             'matrix-interpretation of dimension 2'
             --------------------------------------
             Answer:           YES(?,O(1))
             Input Problem:    DP runtime-complexity with respect to
               Strict Rules: {is_empty^#(cons(x, l)) -> c_1()}
               Weak Rules: {}
             
             Proof Output:    
               The following argument positions are usable:
                 Uargs(cons) = {}, Uargs(is_empty^#) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                cons(x1, x2) = [0 0] x1 + [0 0] x2 + [2]
                               [0 0]      [0 0]      [2]
                is_empty^#(x1) = [2 0] x1 + [7]
                                 [2 2]      [7]
                c_1() = [0]
                        [1]
           
           * Path {4}: YES(?,O(n^2))
             -----------------------
             
             The usable rules of this path are empty.
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {},
                 Uargs(c_4) = {}, Uargs(ifappend^#) = {}, Uargs(c_5) = {},
                 Uargs(c_6) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [0 0] x1 + [0]
                               [0 0]      [0]
                nil() = [0]
                        [0]
                true() = [0]
                         [0]
                cons(x1, x2) = [1 1] x1 + [1 1] x2 + [0]
                               [0 1]      [0 1]      [0]
                false() = [0]
                          [0]
                hd(x1) = [0 0] x1 + [0]
                         [0 0]      [0]
                tl(x1) = [0 0] x1 + [0]
                         [0 0]      [0]
                append(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                                 [0 0]      [0 0]      [0]
                ifappend(x1, x2, x3) = [0 0] x1 + [0 0] x2 + [0 0] x3 + [0]
                                       [0 0]      [0 0]      [0 0]      [0]
                is_empty^#(x1) = [0 0] x1 + [0]
                                 [0 0]      [0]
                c_0() = [0]
                        [0]
                c_1() = [0]
                        [0]
                hd^#(x1) = [0 0] x1 + [0]
                           [0 0]      [0]
                c_2(x1) = [0 0] x1 + [0]
                          [0 0]      [0]
                tl^#(x1) = [3 3] x1 + [0]
                           [0 0]      [0]
                c_3(x1, x2) = [1 0] x1 + [1 0] x2 + [0]
                              [0 0]      [0 0]      [0]
                append^#(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                                   [0 0]      [0 0]      [0]
                c_4(x1) = [0 0] x1 + [0]
                          [0 0]      [0]
                ifappend^#(x1, x2, x3) = [0 0] x1 + [0 0] x2 + [0 0] x3 + [0]
                                         [0 0]      [0 0]      [0 0]      [0]
                c_5(x1) = [0 0] x1 + [0]
                          [0 0]      [0]
                c_6(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                              [0 0]      [0 0]      [0]
             
             We apply the sub-processor on the resulting sub-problem:
             
             'matrix-interpretation of dimension 2'
             --------------------------------------
             Answer:           YES(?,O(n^1))
             Input Problem:    DP runtime-complexity with respect to
               Strict Rules: {tl^#(cons(x, l)) -> c_3(x, l)}
               Weak Rules: {}
             
             Proof Output:    
               The following argument positions are usable:
                 Uargs(cons) = {}, Uargs(tl^#) = {}, Uargs(c_3) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                cons(x1, x2) = [1 2] x1 + [1 2] x2 + [0]
                               [0 0]      [0 0]      [0]
                tl^#(x1) = [2 0] x1 + [7]
                           [0 0]      [7]
                c_3(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                              [0 0]      [0 0]      [1]
           
           * Path {5,7}: MAYBE
             -----------------
             
             The usable rules for this path are:
             
               {  is_empty(nil()) -> true()
                , is_empty(cons(x, l)) -> false()
                , tl(cons(x, l)) -> cons(x, l)}
             
             The weight gap principle does not apply:
               The input cannot be shown compatible
             Complexity induced by the adequate RMI: MAYBE
             
             We apply the sub-processor on the resulting sub-problem:
             
             'matrix-interpretation of dimension 2'
             --------------------------------------
             Answer:           MAYBE
             Input Problem:    runtime-complexity with respect to
               Rules:
                 {  append^#(l1, l2) -> c_4(ifappend^#(l1, l2, is_empty(l1)))
                  , ifappend^#(l1, l2, false()) ->
                    c_6(hd^#(l1), append^#(tl(l1), l2))
                  , is_empty(nil()) -> true()
                  , is_empty(cons(x, l)) -> false()
                  , tl(cons(x, l)) -> cons(x, l)}
             
             Proof Output:    
               The input cannot be shown compatible
           
           * Path {5,7}->{3}: NA
             -------------------
             
             The usable rules for this path are:
             
               {  is_empty(nil()) -> true()
                , is_empty(cons(x, l)) -> false()
                , tl(cons(x, l)) -> cons(x, l)}
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {1}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {1}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {1}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {1},
                 Uargs(c_4) = {1}, Uargs(ifappend^#) = {1, 3}, Uargs(c_5) = {},
                 Uargs(c_6) = {1, 2}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [2 0] x1 + [3]
                               [3 3]      [3]
                nil() = [0]
                        [0]
                true() = [0]
                         [1]
                cons(x1, x2) = [1 0] x1 + [1 0] x2 + [0]
                               [0 0]      [0 0]      [0]
                false() = [0]
                          [1]
                hd(x1) = [0 0] x1 + [0]
                         [0 0]      [0]
                tl(x1) = [2 0] x1 + [3]
                         [0 0]      [3]
                append(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                                 [0 0]      [0 0]      [0]
                ifappend(x1, x2, x3) = [0 0] x1 + [0 0] x2 + [0 0] x3 + [0]
                                       [0 0]      [0 0]      [0 0]      [0]
                is_empty^#(x1) = [0 0] x1 + [0]
                                 [0 0]      [0]
                c_0() = [0]
                        [0]
                c_1() = [0]
                        [0]
                hd^#(x1) = [3 3] x1 + [0]
                           [0 0]      [0]
                c_2(x1) = [1 0] x1 + [0]
                          [0 0]      [0]
                tl^#(x1) = [0 0] x1 + [0]
                           [0 0]      [0]
                c_3(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                              [0 0]      [0 0]      [0]
                append^#(x1, x2) = [3 0] x1 + [0 0] x2 + [0]
                                   [0 0]      [0 0]      [0]
                c_4(x1) = [1 0] x1 + [0]
                          [0 1]      [0]
                ifappend^#(x1, x2, x3) = [3 0] x1 + [0 0] x2 + [3 0] x3 + [0]
                                         [0 0]      [0 0]      [0 0]      [0]
                c_5(x1) = [0 0] x1 + [0]
                          [0 0]      [0]
                c_6(x1, x2) = [1 0] x1 + [1 0] x2 + [0]
                              [0 1]      [0 1]      [0]
             Complexity induced by the adequate RMI: YES(?,O(n^1))
             
             We have not generated a proof for the resulting sub-problem.
           
           * Path {5,7}->{6}: NA
             -------------------
             
             The usable rules for this path are:
             
               {  is_empty(nil()) -> true()
                , is_empty(cons(x, l)) -> false()
                , tl(cons(x, l)) -> cons(x, l)}
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {1}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {1}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {1}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {1},
                 Uargs(c_4) = {1}, Uargs(ifappend^#) = {1, 3}, Uargs(c_5) = {},
                 Uargs(c_6) = {1, 2}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [2 0] x1 + [3]
                               [3 3]      [3]
                nil() = [0]
                        [0]
                true() = [0]
                         [1]
                cons(x1, x2) = [1 0] x1 + [1 0] x2 + [0]
                               [0 0]      [0 0]      [0]
                false() = [0]
                          [1]
                hd(x1) = [0 0] x1 + [0]
                         [0 0]      [0]
                tl(x1) = [2 0] x1 + [3]
                         [0 0]      [3]
                append(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                                 [0 0]      [0 0]      [0]
                ifappend(x1, x2, x3) = [0 0] x1 + [0 0] x2 + [0 0] x3 + [0]
                                       [0 0]      [0 0]      [0 0]      [0]
                is_empty^#(x1) = [0 0] x1 + [0]
                                 [0 0]      [0]
                c_0() = [0]
                        [0]
                c_1() = [0]
                        [0]
                hd^#(x1) = [3 0] x1 + [0]
                           [0 0]      [0]
                c_2(x1) = [0 0] x1 + [0]
                          [0 0]      [0]
                tl^#(x1) = [0 0] x1 + [0]
                           [0 0]      [0]
                c_3(x1, x2) = [0 0] x1 + [0 0] x2 + [0]
                              [0 0]      [0 0]      [0]
                append^#(x1, x2) = [3 0] x1 + [0 0] x2 + [0]
                                   [0 0]      [0 0]      [0]
                c_4(x1) = [1 0] x1 + [0]
                          [0 1]      [0]
                ifappend^#(x1, x2, x3) = [3 3] x1 + [0 0] x2 + [3 0] x3 + [0]
                                         [0 0]      [0 0]      [0 0]      [0]
                c_5(x1) = [1 1] x1 + [0]
                          [0 0]      [0]
                c_6(x1, x2) = [1 0] x1 + [1 0] x2 + [0]
                              [0 1]      [0 1]      [0]
             Complexity induced by the adequate RMI: YES(?,O(n^1))
             
             We have not generated a proof for the resulting sub-problem.
    
    3) 'wdg' failed due to the following reason:
         Transformation Details:
         -----------------------
           We have computed the following set of weak (innermost) dependency pairs:
           
             {  1: is_empty^#(nil()) -> c_0()
              , 2: is_empty^#(cons(x, l)) -> c_1()
              , 3: hd^#(cons(x, l)) -> c_2(x)
              , 4: tl^#(cons(x, l)) -> c_3(x, l)
              , 5: append^#(l1, l2) -> c_4(ifappend^#(l1, l2, is_empty(l1)))
              , 6: ifappend^#(l1, l2, true()) -> c_5(l2)
              , 7: ifappend^#(l1, l2, false()) ->
                   c_6(hd^#(l1), append^#(tl(l1), l2))}
           
           Following Dependency Graph (modulo SCCs) was computed. (Answers to
           subproofs are indicated to the right.)
           
             ->{5,7}                                                     [       MAYBE        ]
                |
                |->{3}                                                   [         NA         ]
                |
                `->{6}                                                   [         NA         ]
             
             ->{4}                                                       [   YES(?,O(n^1))    ]
             
             ->{2}                                                       [    YES(?,O(1))     ]
             
             ->{1}                                                       [    YES(?,O(1))     ]
             
           
         
         Sub-problems:
         -------------
           * Path {1}: YES(?,O(1))
             ---------------------
             
             The usable rules of this path are empty.
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {},
                 Uargs(c_4) = {}, Uargs(ifappend^#) = {}, Uargs(c_5) = {},
                 Uargs(c_6) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [0] x1 + [0]
                nil() = [0]
                true() = [0]
                cons(x1, x2) = [0] x1 + [0] x2 + [0]
                false() = [0]
                hd(x1) = [0] x1 + [0]
                tl(x1) = [0] x1 + [0]
                append(x1, x2) = [0] x1 + [0] x2 + [0]
                ifappend(x1, x2, x3) = [0] x1 + [0] x2 + [0] x3 + [0]
                is_empty^#(x1) = [0] x1 + [0]
                c_0() = [0]
                c_1() = [0]
                hd^#(x1) = [0] x1 + [0]
                c_2(x1) = [0] x1 + [0]
                tl^#(x1) = [0] x1 + [0]
                c_3(x1, x2) = [0] x1 + [0] x2 + [0]
                append^#(x1, x2) = [0] x1 + [0] x2 + [0]
                c_4(x1) = [0] x1 + [0]
                ifappend^#(x1, x2, x3) = [0] x1 + [0] x2 + [0] x3 + [0]
                c_5(x1) = [0] x1 + [0]
                c_6(x1, x2) = [0] x1 + [0] x2 + [0]
             
             We apply the sub-processor on the resulting sub-problem:
             
             'matrix-interpretation of dimension 1'
             --------------------------------------
             Answer:           YES(?,O(1))
             Input Problem:    DP runtime-complexity with respect to
               Strict Rules: {is_empty^#(nil()) -> c_0()}
               Weak Rules: {}
             
             Proof Output:    
               The following argument positions are usable:
                 Uargs(is_empty^#) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                nil() = [7]
                is_empty^#(x1) = [1] x1 + [7]
                c_0() = [1]
           
           * Path {2}: YES(?,O(1))
             ---------------------
             
             The usable rules of this path are empty.
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {},
                 Uargs(c_4) = {}, Uargs(ifappend^#) = {}, Uargs(c_5) = {},
                 Uargs(c_6) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [0] x1 + [0]
                nil() = [0]
                true() = [0]
                cons(x1, x2) = [0] x1 + [0] x2 + [0]
                false() = [0]
                hd(x1) = [0] x1 + [0]
                tl(x1) = [0] x1 + [0]
                append(x1, x2) = [0] x1 + [0] x2 + [0]
                ifappend(x1, x2, x3) = [0] x1 + [0] x2 + [0] x3 + [0]
                is_empty^#(x1) = [0] x1 + [0]
                c_0() = [0]
                c_1() = [0]
                hd^#(x1) = [0] x1 + [0]
                c_2(x1) = [0] x1 + [0]
                tl^#(x1) = [0] x1 + [0]
                c_3(x1, x2) = [0] x1 + [0] x2 + [0]
                append^#(x1, x2) = [0] x1 + [0] x2 + [0]
                c_4(x1) = [0] x1 + [0]
                ifappend^#(x1, x2, x3) = [0] x1 + [0] x2 + [0] x3 + [0]
                c_5(x1) = [0] x1 + [0]
                c_6(x1, x2) = [0] x1 + [0] x2 + [0]
             
             We apply the sub-processor on the resulting sub-problem:
             
             'matrix-interpretation of dimension 1'
             --------------------------------------
             Answer:           YES(?,O(1))
             Input Problem:    DP runtime-complexity with respect to
               Strict Rules: {is_empty^#(cons(x, l)) -> c_1()}
               Weak Rules: {}
             
             Proof Output:    
               The following argument positions are usable:
                 Uargs(cons) = {}, Uargs(is_empty^#) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                cons(x1, x2) = [0] x1 + [0] x2 + [7]
                is_empty^#(x1) = [1] x1 + [7]
                c_1() = [1]
           
           * Path {4}: YES(?,O(n^1))
             -----------------------
             
             The usable rules of this path are empty.
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {},
                 Uargs(c_4) = {}, Uargs(ifappend^#) = {}, Uargs(c_5) = {},
                 Uargs(c_6) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [0] x1 + [0]
                nil() = [0]
                true() = [0]
                cons(x1, x2) = [1] x1 + [1] x2 + [0]
                false() = [0]
                hd(x1) = [0] x1 + [0]
                tl(x1) = [0] x1 + [0]
                append(x1, x2) = [0] x1 + [0] x2 + [0]
                ifappend(x1, x2, x3) = [0] x1 + [0] x2 + [0] x3 + [0]
                is_empty^#(x1) = [0] x1 + [0]
                c_0() = [0]
                c_1() = [0]
                hd^#(x1) = [0] x1 + [0]
                c_2(x1) = [0] x1 + [0]
                tl^#(x1) = [3] x1 + [0]
                c_3(x1, x2) = [1] x1 + [1] x2 + [0]
                append^#(x1, x2) = [0] x1 + [0] x2 + [0]
                c_4(x1) = [0] x1 + [0]
                ifappend^#(x1, x2, x3) = [0] x1 + [0] x2 + [0] x3 + [0]
                c_5(x1) = [0] x1 + [0]
                c_6(x1, x2) = [0] x1 + [0] x2 + [0]
             
             We apply the sub-processor on the resulting sub-problem:
             
             'matrix-interpretation of dimension 1'
             --------------------------------------
             Answer:           YES(?,O(n^1))
             Input Problem:    DP runtime-complexity with respect to
               Strict Rules: {tl^#(cons(x, l)) -> c_3(x, l)}
               Weak Rules: {}
             
             Proof Output:    
               The following argument positions are usable:
                 Uargs(cons) = {}, Uargs(tl^#) = {}, Uargs(c_3) = {}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                cons(x1, x2) = [1] x1 + [1] x2 + [5]
                tl^#(x1) = [3] x1 + [0]
                c_3(x1, x2) = [1] x1 + [1] x2 + [0]
           
           * Path {5,7}: MAYBE
             -----------------
             
             The usable rules for this path are:
             
               {  is_empty(nil()) -> true()
                , is_empty(cons(x, l)) -> false()
                , tl(cons(x, l)) -> cons(x, l)}
             
             The weight gap principle does not apply:
               The input cannot be shown compatible
             Complexity induced by the adequate RMI: MAYBE
             
             We apply the sub-processor on the resulting sub-problem:
             
             'matrix-interpretation of dimension 1'
             --------------------------------------
             Answer:           MAYBE
             Input Problem:    runtime-complexity with respect to
               Rules:
                 {  append^#(l1, l2) -> c_4(ifappend^#(l1, l2, is_empty(l1)))
                  , ifappend^#(l1, l2, false()) ->
                    c_6(hd^#(l1), append^#(tl(l1), l2))
                  , is_empty(nil()) -> true()
                  , is_empty(cons(x, l)) -> false()
                  , tl(cons(x, l)) -> cons(x, l)}
             
             Proof Output:    
               The input cannot be shown compatible
           
           * Path {5,7}->{3}: NA
             -------------------
             
             The usable rules for this path are:
             
               {  is_empty(nil()) -> true()
                , is_empty(cons(x, l)) -> false()
                , tl(cons(x, l)) -> cons(x, l)}
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {1}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {1}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {1}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {1},
                 Uargs(c_4) = {1}, Uargs(ifappend^#) = {1, 3}, Uargs(c_5) = {},
                 Uargs(c_6) = {1, 2}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [3] x1 + [3]
                nil() = [1]
                true() = [1]
                cons(x1, x2) = [1] x1 + [1] x2 + [1]
                false() = [1]
                hd(x1) = [0] x1 + [0]
                tl(x1) = [3] x1 + [3]
                append(x1, x2) = [0] x1 + [0] x2 + [0]
                ifappend(x1, x2, x3) = [0] x1 + [0] x2 + [0] x3 + [0]
                is_empty^#(x1) = [0] x1 + [0]
                c_0() = [0]
                c_1() = [0]
                hd^#(x1) = [3] x1 + [0]
                c_2(x1) = [1] x1 + [0]
                tl^#(x1) = [0] x1 + [0]
                c_3(x1, x2) = [0] x1 + [0] x2 + [0]
                append^#(x1, x2) = [3] x1 + [0] x2 + [0]
                c_4(x1) = [1] x1 + [0]
                ifappend^#(x1, x2, x3) = [3] x1 + [0] x2 + [3] x3 + [0]
                c_5(x1) = [0] x1 + [0]
                c_6(x1, x2) = [1] x1 + [1] x2 + [0]
             Complexity induced by the adequate RMI: YES(?,O(n^1))
             
             We have not generated a proof for the resulting sub-problem.
           
           * Path {5,7}->{6}: NA
             -------------------
             
             The usable rules for this path are:
             
               {  is_empty(nil()) -> true()
                , is_empty(cons(x, l)) -> false()
                , tl(cons(x, l)) -> cons(x, l)}
             
             The weightgap principle applies, using the following adequate RMI:
               The following argument positions are usable:
                 Uargs(is_empty) = {1}, Uargs(cons) = {}, Uargs(hd) = {},
                 Uargs(tl) = {1}, Uargs(append) = {}, Uargs(ifappend) = {},
                 Uargs(is_empty^#) = {}, Uargs(hd^#) = {1}, Uargs(c_2) = {},
                 Uargs(tl^#) = {}, Uargs(c_3) = {}, Uargs(append^#) = {1},
                 Uargs(c_4) = {1}, Uargs(ifappend^#) = {1, 3}, Uargs(c_5) = {},
                 Uargs(c_6) = {1, 2}
               We have the following constructor-restricted matrix interpretation:
               Interpretation Functions:
                is_empty(x1) = [1] x1 + [3]
                nil() = [3]
                true() = [1]
                cons(x1, x2) = [1] x1 + [1] x2 + [3]
                false() = [1]
                hd(x1) = [0] x1 + [0]
                tl(x1) = [1] x1 + [3]
                append(x1, x2) = [0] x1 + [0] x2 + [0]
                ifappend(x1, x2, x3) = [0] x1 + [0] x2 + [0] x3 + [0]
                is_empty^#(x1) = [0] x1 + [0]
                c_0() = [0]
                c_1() = [0]
                hd^#(x1) = [3] x1 + [0]
                c_2(x1) = [0] x1 + [0]
                tl^#(x1) = [0] x1 + [0]
                c_3(x1, x2) = [0] x1 + [0] x2 + [0]
                append^#(x1, x2) = [3] x1 + [0] x2 + [0]
                c_4(x1) = [1] x1 + [0]
                ifappend^#(x1, x2, x3) = [3] x1 + [0] x2 + [3] x3 + [0]
                c_5(x1) = [1] x1 + [0]
                c_6(x1, x2) = [1] x1 + [1] x2 + [0]
             Complexity induced by the adequate RMI: YES(?,O(n^1))
             
             We have not generated a proof for the resulting sub-problem.
    
    4) 'matrix-interpretation of dimension 1' failed due to the following reason:
         The input cannot be shown compatible
    
    5) 'Bounds with perSymbol-enrichment and initial automaton 'match'' failed due to the following reason:
         match-boundness of the problem could not be verified.
    
    6) 'Bounds with minimal-enrichment and initial automaton 'match'' failed due to the following reason:
         match-boundness of the problem could not be verified.