We consider the following Problem:

  Strict Trs:
    {  half(0()) -> 0()
     , half(s(0())) -> 0()
     , half(s(s(x))) -> s(half(x))
     , lastbit(0()) -> 0()
     , lastbit(s(0())) -> s(0())
     , lastbit(s(s(x))) -> lastbit(x)
     , zero(0()) -> true()
     , zero(s(x)) -> false()
     , conv(x) -> conviter(x, cons(0(), nil()))
     , conviter(x, l) -> if(zero(x), x, l)
     , if(true(), x, l) -> l
     , if(false(), x, l) -> conviter(half(x), cons(lastbit(x), l))}
  StartTerms: basic terms
  Strategy: innermost

Certificate: YES(?,O(n^1))

Proof:
  We consider the following Problem:
  
    Strict Trs:
      {  half(0()) -> 0()
       , half(s(0())) -> 0()
       , half(s(s(x))) -> s(half(x))
       , lastbit(0()) -> 0()
       , lastbit(s(0())) -> s(0())
       , lastbit(s(s(x))) -> lastbit(x)
       , zero(0()) -> true()
       , zero(s(x)) -> false()
       , conv(x) -> conviter(x, cons(0(), nil()))
       , conviter(x, l) -> if(zero(x), x, l)
       , if(true(), x, l) -> l
       , if(false(), x, l) -> conviter(half(x), cons(lastbit(x), l))}
    StartTerms: basic terms
    Strategy: innermost
  
  Certificate: YES(?,O(n^1))
  
  Proof:
    The weightgap principle applies, where following rules are oriented strictly:
    
    TRS Component:
      {  half(0()) -> 0()
       , half(s(0())) -> 0()
       , lastbit(0()) -> 0()
       , lastbit(s(0())) -> s(0())
       , zero(0()) -> true()
       , zero(s(x)) -> false()}
    
    Interpretation of nonconstant growth:
    -------------------------------------
      The following argument positions are usable:
        Uargs(half) = {}, Uargs(s) = {1}, Uargs(lastbit) = {},
        Uargs(zero) = {}, Uargs(conv) = {}, Uargs(conviter) = {1, 2},
        Uargs(cons) = {1}, Uargs(if) = {1}
      We have the following EDA-non-satisfying and IDA(1)-non-satisfying matrix interpretation:
      Interpretation Functions:
       half(x1) = [0 0] x1 + [1]
                  [0 0]      [1]
       0() = [0]
             [0]
       s(x1) = [1 0] x1 + [0]
               [0 0]      [1]
       lastbit(x1) = [0 0] x1 + [1]
                     [0 0]      [1]
       zero(x1) = [0 0] x1 + [1]
                  [0 0]      [1]
       true() = [0]
                [0]
       false() = [0]
                 [0]
       conv(x1) = [1 1] x1 + [0]
                  [0 0]      [0]
       conviter(x1, x2) = [1 1] x1 + [1 0] x2 + [1]
                          [0 0]      [0 0]      [1]
       cons(x1, x2) = [1 0] x1 + [0 0] x2 + [0]
                      [0 0]      [0 0]      [0]
       nil() = [0]
               [0]
       if(x1, x2, x3) = [1 0] x1 + [1 1] x2 + [0 0] x3 + [0]
                        [0 0]      [0 0]      [0 0]      [1]
    
    The strictly oriented rules are moved into the weak component.
    
    We consider the following Problem:
    
      Strict Trs:
        {  half(s(s(x))) -> s(half(x))
         , lastbit(s(s(x))) -> lastbit(x)
         , conv(x) -> conviter(x, cons(0(), nil()))
         , conviter(x, l) -> if(zero(x), x, l)
         , if(true(), x, l) -> l
         , if(false(), x, l) -> conviter(half(x), cons(lastbit(x), l))}
      Weak Trs:
        {  half(0()) -> 0()
         , half(s(0())) -> 0()
         , lastbit(0()) -> 0()
         , lastbit(s(0())) -> s(0())
         , zero(0()) -> true()
         , zero(s(x)) -> false()}
      StartTerms: basic terms
      Strategy: innermost
    
    Certificate: YES(?,O(n^1))
    
    Proof:
      The weightgap principle applies, where following rules are oriented strictly:
      
      TRS Component: {conv(x) -> conviter(x, cons(0(), nil()))}
      
      Interpretation of nonconstant growth:
      -------------------------------------
        The following argument positions are usable:
          Uargs(half) = {}, Uargs(s) = {1}, Uargs(lastbit) = {},
          Uargs(zero) = {}, Uargs(conv) = {}, Uargs(conviter) = {1, 2},
          Uargs(cons) = {1}, Uargs(if) = {1}
        We have the following EDA-non-satisfying and IDA(1)-non-satisfying matrix interpretation:
        Interpretation Functions:
         half(x1) = [0 0] x1 + [1]
                    [0 0]      [1]
         0() = [0]
               [0]
         s(x1) = [1 0] x1 + [0]
                 [0 0]      [1]
         lastbit(x1) = [0 0] x1 + [1]
                       [0 0]      [1]
         zero(x1) = [0 0] x1 + [0]
                    [0 0]      [1]
         true() = [0]
                  [0]
         false() = [0]
                   [0]
         conv(x1) = [1 1] x1 + [2]
                    [0 0]      [2]
         conviter(x1, x2) = [1 1] x1 + [1 0] x2 + [1]
                            [0 0]      [0 0]      [1]
         cons(x1, x2) = [1 0] x1 + [0 0] x2 + [0]
                        [0 0]      [0 0]      [0]
         nil() = [0]
                 [0]
         if(x1, x2, x3) = [1 0] x1 + [1 1] x2 + [0 0] x3 + [1]
                          [0 0]      [0 0]      [0 0]      [1]
      
      The strictly oriented rules are moved into the weak component.
      
      We consider the following Problem:
      
        Strict Trs:
          {  half(s(s(x))) -> s(half(x))
           , lastbit(s(s(x))) -> lastbit(x)
           , conviter(x, l) -> if(zero(x), x, l)
           , if(true(), x, l) -> l
           , if(false(), x, l) -> conviter(half(x), cons(lastbit(x), l))}
        Weak Trs:
          {  conv(x) -> conviter(x, cons(0(), nil()))
           , half(0()) -> 0()
           , half(s(0())) -> 0()
           , lastbit(0()) -> 0()
           , lastbit(s(0())) -> s(0())
           , zero(0()) -> true()
           , zero(s(x)) -> false()}
        StartTerms: basic terms
        Strategy: innermost
      
      Certificate: YES(?,O(n^1))
      
      Proof:
        The weightgap principle applies, where following rules are oriented strictly:
        
        TRS Component: {if(true(), x, l) -> l}
        
        Interpretation of nonconstant growth:
        -------------------------------------
          The following argument positions are usable:
            Uargs(half) = {}, Uargs(s) = {1}, Uargs(lastbit) = {},
            Uargs(zero) = {}, Uargs(conv) = {}, Uargs(conviter) = {1, 2},
            Uargs(cons) = {1}, Uargs(if) = {1}
          We have the following EDA-non-satisfying and IDA(1)-non-satisfying matrix interpretation:
          Interpretation Functions:
           half(x1) = [0 0] x1 + [1]
                      [0 0]      [1]
           0() = [0]
                 [0]
           s(x1) = [1 0] x1 + [0]
                   [0 0]      [1]
           lastbit(x1) = [0 0] x1 + [1]
                         [0 0]      [1]
           zero(x1) = [0 0] x1 + [0]
                      [0 0]      [1]
           true() = [0]
                    [0]
           false() = [0]
                     [0]
           conv(x1) = [1 1] x1 + [0]
                      [0 0]      [2]
           conviter(x1, x2) = [1 1] x1 + [1 0] x2 + [0]
                              [0 0]      [0 0]      [1]
           cons(x1, x2) = [1 0] x1 + [0 0] x2 + [0]
                          [0 1]      [0 0]      [0]
           nil() = [0]
                   [0]
           if(x1, x2, x3) = [1 0] x1 + [1 1] x2 + [1 0] x3 + [1]
                            [0 0]      [0 0]      [0 1]      [1]
        
        The strictly oriented rules are moved into the weak component.
        
        We consider the following Problem:
        
          Strict Trs:
            {  half(s(s(x))) -> s(half(x))
             , lastbit(s(s(x))) -> lastbit(x)
             , conviter(x, l) -> if(zero(x), x, l)
             , if(false(), x, l) -> conviter(half(x), cons(lastbit(x), l))}
          Weak Trs:
            {  if(true(), x, l) -> l
             , conv(x) -> conviter(x, cons(0(), nil()))
             , half(0()) -> 0()
             , half(s(0())) -> 0()
             , lastbit(0()) -> 0()
             , lastbit(s(0())) -> s(0())
             , zero(0()) -> true()
             , zero(s(x)) -> false()}
          StartTerms: basic terms
          Strategy: innermost
        
        Certificate: YES(?,O(n^1))
        
        Proof:
          The weightgap principle applies, where following rules are oriented strictly:
          
          TRS Component:
            {if(false(), x, l) -> conviter(half(x), cons(lastbit(x), l))}
          
          Interpretation of nonconstant growth:
          -------------------------------------
            The following argument positions are usable:
              Uargs(half) = {}, Uargs(s) = {1}, Uargs(lastbit) = {},
              Uargs(zero) = {}, Uargs(conv) = {}, Uargs(conviter) = {1, 2},
              Uargs(cons) = {1}, Uargs(if) = {1}
            We have the following EDA-non-satisfying and IDA(1)-non-satisfying matrix interpretation:
            Interpretation Functions:
             half(x1) = [0 0] x1 + [3]
                        [0 0]      [0]
             0() = [0]
                   [0]
             s(x1) = [1 0] x1 + [0]
                     [0 0]      [0]
             lastbit(x1) = [0 0] x1 + [0]
                           [0 0]      [1]
             zero(x1) = [0 0] x1 + [3]
                        [0 0]      [1]
             true() = [0]
                      [0]
             false() = [3]
                       [0]
             conv(x1) = [1 0] x1 + [2]
                        [0 1]      [2]
             conviter(x1, x2) = [1 0] x1 + [1 0] x2 + [0]
                                [0 0]      [0 0]      [1]
             cons(x1, x2) = [1 0] x1 + [0 0] x2 + [2]
                            [0 0]      [0 0]      [0]
             nil() = [0]
                     [0]
             if(x1, x2, x3) = [1 0] x1 + [1 0] x2 + [1 0] x3 + [3]
                              [0 0]      [0 1]      [0 1]      [1]
          
          The strictly oriented rules are moved into the weak component.
          
          We consider the following Problem:
          
            Strict Trs:
              {  half(s(s(x))) -> s(half(x))
               , lastbit(s(s(x))) -> lastbit(x)
               , conviter(x, l) -> if(zero(x), x, l)}
            Weak Trs:
              {  if(false(), x, l) -> conviter(half(x), cons(lastbit(x), l))
               , if(true(), x, l) -> l
               , conv(x) -> conviter(x, cons(0(), nil()))
               , half(0()) -> 0()
               , half(s(0())) -> 0()
               , lastbit(0()) -> 0()
               , lastbit(s(0())) -> s(0())
               , zero(0()) -> true()
               , zero(s(x)) -> false()}
            StartTerms: basic terms
            Strategy: innermost
          
          Certificate: YES(?,O(n^1))
          
          Proof:
            The weightgap principle applies, where following rules are oriented strictly:
            
            TRS Component: {lastbit(s(s(x))) -> lastbit(x)}
            
            Interpretation of nonconstant growth:
            -------------------------------------
              The following argument positions are usable:
                Uargs(half) = {}, Uargs(s) = {1}, Uargs(lastbit) = {},
                Uargs(zero) = {}, Uargs(conv) = {}, Uargs(conviter) = {1, 2},
                Uargs(cons) = {1}, Uargs(if) = {1}
              We have the following EDA-non-satisfying and IDA(1)-non-satisfying matrix interpretation:
              Interpretation Functions:
               half(x1) = [0 0] x1 + [0]
                          [0 0]      [0]
               0() = [0]
                     [0]
               s(x1) = [1 0] x1 + [3]
                       [0 0]      [2]
               lastbit(x1) = [1 0] x1 + [1]
                             [0 0]      [3]
               zero(x1) = [0 1] x1 + [2]
                          [0 0]      [3]
               true() = [0]
                        [0]
               false() = [2]
                         [3]
               conv(x1) = [1 2] x1 + [3]
                          [0 0]      [0]
               conviter(x1, x2) = [1 1] x1 + [1 0] x2 + [0]
                                  [0 0]      [0 1]      [0]
               cons(x1, x2) = [1 0] x1 + [0 0] x2 + [3]
                              [0 0]      [0 0]      [0]
               nil() = [0]
                       [0]
               if(x1, x2, x3) = [1 2] x1 + [1 0] x2 + [1 0] x3 + [0]
                                [0 0]      [0 1]      [0 1]      [0]
            
            The strictly oriented rules are moved into the weak component.
            
            We consider the following Problem:
            
              Strict Trs:
                {  half(s(s(x))) -> s(half(x))
                 , conviter(x, l) -> if(zero(x), x, l)}
              Weak Trs:
                {  lastbit(s(s(x))) -> lastbit(x)
                 , if(false(), x, l) -> conviter(half(x), cons(lastbit(x), l))
                 , if(true(), x, l) -> l
                 , conv(x) -> conviter(x, cons(0(), nil()))
                 , half(0()) -> 0()
                 , half(s(0())) -> 0()
                 , lastbit(0()) -> 0()
                 , lastbit(s(0())) -> s(0())
                 , zero(0()) -> true()
                 , zero(s(x)) -> false()}
              StartTerms: basic terms
              Strategy: innermost
            
            Certificate: YES(?,O(n^1))
            
            Proof:
              The weightgap principle applies, where following rules are oriented strictly:
              
              TRS Component: {conviter(x, l) -> if(zero(x), x, l)}
              
              Interpretation of nonconstant growth:
              -------------------------------------
                The following argument positions are usable:
                  Uargs(half) = {}, Uargs(s) = {1}, Uargs(lastbit) = {},
                  Uargs(zero) = {}, Uargs(conv) = {}, Uargs(conviter) = {1, 2},
                  Uargs(cons) = {1}, Uargs(if) = {1}
                We have the following EDA-non-satisfying and IDA(1)-non-satisfying matrix interpretation:
                Interpretation Functions:
                 half(x1) = [0 0] x1 + [0]
                            [0 0]      [0]
                 0() = [0]
                       [0]
                 s(x1) = [1 0] x1 + [0]
                         [0 0]      [2]
                 lastbit(x1) = [0 0] x1 + [0]
                               [0 0]      [3]
                 zero(x1) = [0 2] x1 + [0]
                            [0 1]      [2]
                 true() = [0]
                          [0]
                 false() = [1]
                           [0]
                 conv(x1) = [1 2] x1 + [1]
                            [0 0]      [2]
                 conviter(x1, x2) = [1 2] x1 + [1 0] x2 + [1]
                                    [0 0]      [0 1]      [1]
                 cons(x1, x2) = [1 0] x1 + [0 0] x2 + [0]
                                [0 0]      [0 0]      [0]
                 nil() = [0]
                         [0]
                 if(x1, x2, x3) = [1 0] x1 + [0 0] x2 + [1 0] x3 + [0]
                                  [0 0]      [0 0]      [0 1]      [1]
              
              The strictly oriented rules are moved into the weak component.
              
              We consider the following Problem:
              
                Strict Trs: {half(s(s(x))) -> s(half(x))}
                Weak Trs:
                  {  conviter(x, l) -> if(zero(x), x, l)
                   , lastbit(s(s(x))) -> lastbit(x)
                   , if(false(), x, l) -> conviter(half(x), cons(lastbit(x), l))
                   , if(true(), x, l) -> l
                   , conv(x) -> conviter(x, cons(0(), nil()))
                   , half(0()) -> 0()
                   , half(s(0())) -> 0()
                   , lastbit(0()) -> 0()
                   , lastbit(s(0())) -> s(0())
                   , zero(0()) -> true()
                   , zero(s(x)) -> false()}
                StartTerms: basic terms
                Strategy: innermost
              
              Certificate: YES(?,O(n^1))
              
              Proof:
                The weightgap principle applies, where following rules are oriented strictly:
                
                TRS Component: {half(s(s(x))) -> s(half(x))}
                
                Interpretation of nonconstant growth:
                -------------------------------------
                  The following argument positions are usable:
                    Uargs(half) = {}, Uargs(s) = {1}, Uargs(lastbit) = {},
                    Uargs(zero) = {}, Uargs(conv) = {}, Uargs(conviter) = {1, 2},
                    Uargs(cons) = {1}, Uargs(if) = {1}
                  We have the following EDA-non-satisfying and IDA(1)-non-satisfying matrix interpretation:
                  Interpretation Functions:
                   half(x1) = [1 0] x1 + [0]
                              [0 1]      [0]
                   0() = [0]
                         [0]
                   s(x1) = [1 1] x1 + [0]
                           [0 0]      [1]
                   lastbit(x1) = [0 0] x1 + [0]
                                 [0 0]      [1]
                   zero(x1) = [0 0] x1 + [0]
                              [0 0]      [0]
                   true() = [0]
                            [0]
                   false() = [0]
                             [0]
                   conv(x1) = [1 0] x1 + [0]
                              [0 1]      [1]
                   conviter(x1, x2) = [1 0] x1 + [1 0] x2 + [0]
                                      [0 1]      [0 1]      [1]
                   cons(x1, x2) = [1 0] x1 + [0 0] x2 + [0]
                                  [0 0]      [0 0]      [0]
                   nil() = [0]
                           [0]
                   if(x1, x2, x3) = [1 0] x1 + [1 0] x2 + [1 0] x3 + [0]
                                    [0 0]      [0 1]      [0 1]      [1]
                
                The strictly oriented rules are moved into the weak component.
                
                We consider the following Problem:
                
                  Weak Trs:
                    {  half(s(s(x))) -> s(half(x))
                     , conviter(x, l) -> if(zero(x), x, l)
                     , lastbit(s(s(x))) -> lastbit(x)
                     , if(false(), x, l) -> conviter(half(x), cons(lastbit(x), l))
                     , if(true(), x, l) -> l
                     , conv(x) -> conviter(x, cons(0(), nil()))
                     , half(0()) -> 0()
                     , half(s(0())) -> 0()
                     , lastbit(0()) -> 0()
                     , lastbit(s(0())) -> s(0())
                     , zero(0()) -> true()
                     , zero(s(x)) -> false()}
                  StartTerms: basic terms
                  Strategy: innermost
                
                Certificate: YES(O(1),O(1))
                
                Proof:
                  We consider the following Problem:
                  
                    Weak Trs:
                      {  half(s(s(x))) -> s(half(x))
                       , conviter(x, l) -> if(zero(x), x, l)
                       , lastbit(s(s(x))) -> lastbit(x)
                       , if(false(), x, l) -> conviter(half(x), cons(lastbit(x), l))
                       , if(true(), x, l) -> l
                       , conv(x) -> conviter(x, cons(0(), nil()))
                       , half(0()) -> 0()
                       , half(s(0())) -> 0()
                       , lastbit(0()) -> 0()
                       , lastbit(s(0())) -> s(0())
                       , zero(0()) -> true()
                       , zero(s(x)) -> false()}
                    StartTerms: basic terms
                    Strategy: innermost
                  
                  Certificate: YES(O(1),O(1))
                  
                  Proof:
                    Empty rules are trivially bounded

Hurray, we answered YES(?,O(n^1))