MAYBE
* Step 1: UnreachableRules MAYBE
    + Considered Problem:
        Rules:
          0. f7(A,B)  -> f7(C,B)  [0 >= 1 + A] (?,1)
          1. f7(A,B)  -> f7(C,B)  [A >= 1]     (?,1)
          2. f13(A,B) -> f13(A,B) True         (?,1)
          3. f15(A,B) -> f17(A,B) True         (?,1)
          4. f7(A,B)  -> f13(0,1) [A = 0]      (?,1)
          5. f0(A,B)  -> f7(C,1)  True         (1,1)
        Signature:
          {(f0,2);(f13,2);(f15,2);(f17,2);(f7,2)}
        Flow Graph:
          [0->{0,1,4},1->{0,1,4},2->{2},3->{},4->{2},5->{0,1,4}]
        
    + Applied Processor:
        UnreachableRules
    + Details:
        Following transitions are not reachable from the starting states and are revomed: [3]
* Step 2: FromIts MAYBE
    + Considered Problem:
        Rules:
          0. f7(A,B)  -> f7(C,B)  [0 >= 1 + A] (?,1)
          1. f7(A,B)  -> f7(C,B)  [A >= 1]     (?,1)
          2. f13(A,B) -> f13(A,B) True         (?,1)
          4. f7(A,B)  -> f13(0,1) [A = 0]      (?,1)
          5. f0(A,B)  -> f7(C,1)  True         (1,1)
        Signature:
          {(f0,2);(f13,2);(f15,2);(f17,2);(f7,2)}
        Flow Graph:
          [0->{0,1,4},1->{0,1,4},2->{2},4->{2},5->{0,1,4}]
        
    + Applied Processor:
        FromIts
    + Details:
        ()
* Step 3: AddSinks MAYBE
    + Considered Problem:
        Rules:
          f7(A,B)  -> f7(C,B)   [0 >= 1 + A]
          f7(A,B)  -> f7(C,B)   [A >= 1]
          f13(A,B) -> f13(A,B)  True
          f7(A,B)  -> f13(0,1)  [A = 0]
          f0(A,B)  -> f7(C,1)   True
        Signature:
          {(f0,2);(f13,2);(f15,2);(f17,2);(f7,2)}
        Rule Graph:
          [0->{0,1,4},1->{0,1,4},2->{2},4->{2},5->{0,1,4}]
    + Applied Processor:
        AddSinks
    + Details:
        ()
* Step 4: Failure MAYBE
  + Considered Problem:
      Rules:
        f7(A,B)  -> f7(C,B)         [0 >= 1 + A]
        f7(A,B)  -> f7(C,B)         [A >= 1]
        f13(A,B) -> f13(A,B)        True
        f7(A,B)  -> f13(0,1)        [A = 0]
        f0(A,B)  -> f7(C,1)         True
        f13(A,B) -> exitus616(A,B)  True
      Signature:
        {(exitus616,2);(f0,2);(f13,2);(f15,2);(f17,2);(f7,2)}
      Rule Graph:
        [0->{0,1,4},1->{0,1,4},2->{2,6},4->{2},5->{0,1,4}]
  + Applied Processor:
      Decompose Greedy
  + Details:
      We construct a looptree:
        P: [0,1,2,4,5,6]
        |
        +- p:[0,1] c: []
        |
        `- p:[2] c: []
MAYBE