MAYBE
* Step 1: FromIts MAYBE
    + Considered Problem:
        Rules:
          0. f0(A,B,C) -> f1(0,B,C)      True                                   (1,1)
          1. f1(A,B,C) -> f1(A,-1 + B,D) [-1*A >= 0 && A >= 0 && B >= 1]        (?,1)
          2. f1(A,B,C) -> f4(A,B,D)      [-1*A >= 0 && A >= 0 && 0 >= B]        (?,1)
          3. f4(A,B,C) -> f4(1,B,D)      [-1*B >= 0 && A + -1*B >= 0 && A >= 0] (?,1)
        Signature:
          {(f0,3);(f1,3);(f4,3)}
        Flow Graph:
          [0->{1,2},1->{1,2},2->{3},3->{3}]
        
    + Applied Processor:
        FromIts
    + Details:
        ()
* Step 2: AddSinks MAYBE
    + Considered Problem:
        Rules:
          f0(A,B,C) -> f1(0,B,C)       True
          f1(A,B,C) -> f1(A,-1 + B,D)  [-1*A >= 0 && A >= 0 && B >= 1]
          f1(A,B,C) -> f4(A,B,D)       [-1*A >= 0 && A >= 0 && 0 >= B]
          f4(A,B,C) -> f4(1,B,D)       [-1*B >= 0 && A + -1*B >= 0 && A >= 0]
        Signature:
          {(f0,3);(f1,3);(f4,3)}
        Rule Graph:
          [0->{1,2},1->{1,2},2->{3},3->{3}]
    + Applied Processor:
        AddSinks
    + Details:
        ()
* Step 3: Failure MAYBE
  + Considered Problem:
      Rules:
        f0(A,B,C) -> f1(0,B,C)         True
        f1(A,B,C) -> f1(A,-1 + B,D)    [-1*A >= 0 && A >= 0 && B >= 1]
        f1(A,B,C) -> f4(A,B,D)         [-1*A >= 0 && A >= 0 && 0 >= B]
        f4(A,B,C) -> f4(1,B,D)         [-1*B >= 0 && A + -1*B >= 0 && A >= 0]
        f4(A,B,C) -> exitus616(A,B,C)  True
      Signature:
        {(exitus616,3);(f0,3);(f1,3);(f4,3)}
      Rule Graph:
        [0->{1,2},1->{1,2},2->{3},3->{3,4}]
  + Applied Processor:
      Decompose Greedy
  + Details:
      We construct a looptree:
        P: [0,1,2,3,4]
        |
        +- p:[1] c: [1]
        |
        `- p:[3] c: []
MAYBE