WORST_CASE(?, O(1))

Initial complexity problem:
1:	T:
		(Comp: ?, Cost: 1)    f0(Ar_0, Ar_1) -> Com_1(f5(2, 4))
		(Comp: ?, Cost: 1)    f5(Ar_0, Ar_1) -> Com_1(f5(Ar_0 + 2, Ar_0 + 4)) [ 19 >= Ar_0 ]
		(Comp: ?, Cost: 1)    f5(Ar_0, Ar_1) -> Com_1(f8(Ar_0, Ar_1)) [ Ar_0 >= 20 ]
		(Comp: 1, Cost: 0)    koat_start(Ar_0, Ar_1) -> Com_1(f0(Ar_0, Ar_1)) [ 0 <= 0 ]
	start location:	koat_start
	leaf cost:	0

Repeatedly propagating knowledge in problem 1 produces the following problem:
2:	T:
		(Comp: 1, Cost: 1)    f0(Ar_0, Ar_1) -> Com_1(f5(2, 4))
		(Comp: ?, Cost: 1)    f5(Ar_0, Ar_1) -> Com_1(f5(Ar_0 + 2, Ar_0 + 4)) [ 19 >= Ar_0 ]
		(Comp: ?, Cost: 1)    f5(Ar_0, Ar_1) -> Com_1(f8(Ar_0, Ar_1)) [ Ar_0 >= 20 ]
		(Comp: 1, Cost: 0)    koat_start(Ar_0, Ar_1) -> Com_1(f0(Ar_0, Ar_1)) [ 0 <= 0 ]
	start location:	koat_start
	leaf cost:	0

A polynomial rank function with
	Pol(f0) = 1
	Pol(f5) = 1
	Pol(f8) = 0
	Pol(koat_start) = 1
orients all transitions weakly and the transition
	f5(Ar_0, Ar_1) -> Com_1(f8(Ar_0, Ar_1)) [ Ar_0 >= 20 ]
strictly and produces the following problem:
3:	T:
		(Comp: 1, Cost: 1)    f0(Ar_0, Ar_1) -> Com_1(f5(2, 4))
		(Comp: ?, Cost: 1)    f5(Ar_0, Ar_1) -> Com_1(f5(Ar_0 + 2, Ar_0 + 4)) [ 19 >= Ar_0 ]
		(Comp: 1, Cost: 1)    f5(Ar_0, Ar_1) -> Com_1(f8(Ar_0, Ar_1)) [ Ar_0 >= 20 ]
		(Comp: 1, Cost: 0)    koat_start(Ar_0, Ar_1) -> Com_1(f0(Ar_0, Ar_1)) [ 0 <= 0 ]
	start location:	koat_start
	leaf cost:	0

A polynomial rank function with
	Pol(f0) = 18
	Pol(f5) = -V_1 + 20
	Pol(f8) = -V_1 + 20
	Pol(koat_start) = 18
orients all transitions weakly and the transition
	f5(Ar_0, Ar_1) -> Com_1(f5(Ar_0 + 2, Ar_0 + 4)) [ 19 >= Ar_0 ]
strictly and produces the following problem:
4:	T:
		(Comp: 1, Cost: 1)     f0(Ar_0, Ar_1) -> Com_1(f5(2, 4))
		(Comp: 18, Cost: 1)    f5(Ar_0, Ar_1) -> Com_1(f5(Ar_0 + 2, Ar_0 + 4)) [ 19 >= Ar_0 ]
		(Comp: 1, Cost: 1)     f5(Ar_0, Ar_1) -> Com_1(f8(Ar_0, Ar_1)) [ Ar_0 >= 20 ]
		(Comp: 1, Cost: 0)     koat_start(Ar_0, Ar_1) -> Com_1(f0(Ar_0, Ar_1)) [ 0 <= 0 ]
	start location:	koat_start
	leaf cost:	0

Complexity upper bound 20

Time: 0.511 sec (SMT: 0.498 sec)