YES(?,O(1))
* Step 1: UnsatPaths WORST_CASE(?,O(1))
    + Considered Problem:
        Rules:
          0. start(A,B) -> f0(A,B) True                  (1,1)
          1. f0(A,B)    -> f0(A,A) [A >= 1 && B = 0]     (?,1)
          2. f0(A,B)    -> f0(A,A) [0 >= 1 + A && B = 0] (?,1)
        Signature:
          {(f0,2);(start,2)}
        Flow Graph:
          [0->{1,2},1->{1,2},2->{1,2}]
        
    + Applied Processor:
        UnsatPaths
    + Details:
        We remove following edges from the transition graph: [(1,1),(1,2),(2,1),(2,2)]
* Step 2: FromIts WORST_CASE(?,O(1))
    + Considered Problem:
        Rules:
          0. start(A,B) -> f0(A,B) True                  (1,1)
          1. f0(A,B)    -> f0(A,A) [A >= 1 && B = 0]     (?,1)
          2. f0(A,B)    -> f0(A,A) [0 >= 1 + A && B = 0] (?,1)
        Signature:
          {(f0,2);(start,2)}
        Flow Graph:
          [0->{1,2},1->{},2->{}]
        
    + Applied Processor:
        FromIts
    + Details:
        ()
* Step 3: AddSinks WORST_CASE(?,O(1))
    + Considered Problem:
        Rules:
          start(A,B) -> f0(A,B)  True
          f0(A,B)    -> f0(A,A)  [A >= 1 && B = 0]
          f0(A,B)    -> f0(A,A)  [0 >= 1 + A && B = 0]
        Signature:
          {(f0,2);(start,2)}
        Rule Graph:
          [0->{1,2},1->{},2->{}]
    + Applied Processor:
        AddSinks
    + Details:
        ()
* Step 4: Decompose WORST_CASE(?,O(1))
    + Considered Problem:
        Rules:
          start(A,B) -> f0(A,B)         True
          f0(A,B)    -> f0(A,A)         [A >= 1 && B = 0]
          f0(A,B)    -> f0(A,A)         [0 >= 1 + A && B = 0]
          f0(A,B)    -> exitus616(A,B)  True
          f0(A,B)    -> exitus616(A,B)  True
        Signature:
          {(exitus616,2);(f0,2);(start,2)}
        Rule Graph:
          [0->{1,2},1->{4},2->{3}]
    + Applied Processor:
        Decompose Greedy
    + Details:
        We construct a looptree:
          P: [0,1,2,3,4]
* Step 5: AbstractSize WORST_CASE(?,O(1))
    + Considered Problem:
        (Rules:
          start(A,B) -> f0(A,B)         True
          f0(A,B)    -> f0(A,A)         [A >= 1 && B = 0]
          f0(A,B)    -> f0(A,A)         [0 >= 1 + A && B = 0]
          f0(A,B)    -> exitus616(A,B)  True
          f0(A,B)    -> exitus616(A,B)  True
        Signature:
          {(exitus616,2);(f0,2);(start,2)}
        Rule Graph:
          [0->{1,2},1->{4},2->{3}]
        ,We construct a looptree:
          P: [0,1,2,3,4])
    + Applied Processor:
        AbstractSize Minimize
    + Details:
        ()
* Step 6: AbstractFlow WORST_CASE(?,O(1))
    + Considered Problem:
        Program:
          Domain: [A,B]
           start  ~>  f0          [A <= A, B <= B]
           f0     ~>  f0          [A <= A, B <= A]
           f0     ~>  f0          [A <= A, B <= A]
           f0     ~>  exitus616   [A <= A, B <= B]
           f0     ~>  exitus616   [A <= A, B <= B]
    + Applied Processor:
        AbstractFlow
    + Details:
        ()
* Step 7: Lare WORST_CASE(?,O(1))
    + Considered Problem:
        Program:
          Domain: [tick,huge,K,A,B]
           start  ~>  f0          []
           f0     ~>  f0          [A ~=> B]
           f0     ~>  f0          [A ~=> B]
           f0     ~>  exitus616   []
           f0     ~>  exitus616   []
    + Applied Processor:
        Lare
    + Details:
         start  ~>  exitus616   [A ~=> B]

YES(?,O(1))