YES(?, 17)

Initial complexity problem:
1:	T:
		(1, 1)    f0(a, b, c) -> f8(0, b, c)
		(?, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a /\ 0 >= d ]
		(?, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a ]
		(?, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a /\ 0 >= e + 1 ]
		(?, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a ]
		(?, 1)    f23(a, b, c) -> f23(a + 1, b, c) [ 0 >= a ]
		(?, 1)    f28(a, b, c) -> f23(a + 1, b, c)
		(?, 1)    f28(a, b, c) -> f23(a + 1, b, c) [ 0 >= d + 1 ]
		(?, 1)    f23(a, b, c) -> f38(a, b, c) [ a >= 1 ]
		(?, 1)    f8(a, b, c) -> f8(a + 1, a, c) [ 0 >= a ]
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c)
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c) [ 0 >= d + 1 ]
		(?, 1)    f8(a, b, c) -> f23(0, b, c) [ a >= 1 ]
	start location:	f0
	leaf cost:	0

Repeatedly removing leaves of the complexity graph in problem 1 produces the following problem:
2:	T:
		(1, 1)    f0(a, b, c) -> f8(0, b, c)
		(?, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a /\ 0 >= d ]
		(?, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a ]
		(?, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a /\ 0 >= e + 1 ]
		(?, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a ]
		(?, 1)    f23(a, b, c) -> f23(a + 1, b, c) [ 0 >= a ]
		(?, 1)    f28(a, b, c) -> f23(a + 1, b, c)
		(?, 1)    f28(a, b, c) -> f23(a + 1, b, c) [ 0 >= d + 1 ]
		(?, 1)    f8(a, b, c) -> f8(a + 1, a, c) [ 0 >= a ]
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c)
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c) [ 0 >= d + 1 ]
		(?, 1)    f8(a, b, c) -> f23(0, b, c) [ a >= 1 ]
	start location:	f0
	leaf cost:	1

A polynomial rank function with
	Pol(f0) = 1
	Pol(f8) = 1
	Pol(f14) = 1
	Pol(f23) = -1
	Pol(f28) = -1
orients all transitions weakly and the transition
	f8(a, b, c) -> f23(0, b, c) [ a >= 1 ]
strictly and produces the following problem:
3:	T:
		(1, 1)    f0(a, b, c) -> f8(0, b, c)
		(?, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a /\ 0 >= d ]
		(?, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a ]
		(?, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a /\ 0 >= e + 1 ]
		(?, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a ]
		(?, 1)    f23(a, b, c) -> f23(a + 1, b, c) [ 0 >= a ]
		(?, 1)    f28(a, b, c) -> f23(a + 1, b, c)
		(?, 1)    f28(a, b, c) -> f23(a + 1, b, c) [ 0 >= d + 1 ]
		(?, 1)    f8(a, b, c) -> f8(a + 1, a, c) [ 0 >= a ]
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c)
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c) [ 0 >= d + 1 ]
		(1, 1)    f8(a, b, c) -> f23(0, b, c) [ a >= 1 ]
	start location:	f0
	leaf cost:	1

A polynomial rank function with
	Pol(f0) = 1
	Pol(f8) = 1
	Pol(f14) = 1
	Pol(f23) = -2*V_1 + 1
	Pol(f28) = -2*V_1
orients all transitions weakly and the transitions
	f23(a, b, c) -> f28(a, b, d) [ 0 >= a ]
	f23(a, b, c) -> f23(a + 1, b, c) [ 0 >= a ]
strictly and produces the following problem:
4:	T:
		(1, 1)    f0(a, b, c) -> f8(0, b, c)
		(?, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a /\ 0 >= d ]
		(?, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a ]
		(?, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a /\ 0 >= e + 1 ]
		(1, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a ]
		(1, 1)    f23(a, b, c) -> f23(a + 1, b, c) [ 0 >= a ]
		(?, 1)    f28(a, b, c) -> f23(a + 1, b, c)
		(?, 1)    f28(a, b, c) -> f23(a + 1, b, c) [ 0 >= d + 1 ]
		(?, 1)    f8(a, b, c) -> f8(a + 1, a, c) [ 0 >= a ]
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c)
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c) [ 0 >= d + 1 ]
		(1, 1)    f8(a, b, c) -> f23(0, b, c) [ a >= 1 ]
	start location:	f0
	leaf cost:	1

A polynomial rank function with
	Pol(f0) = 1
	Pol(f8) = 1
	Pol(f14) = 1
	Pol(f23) = -3*V_1 + 1
	Pol(f28) = -3*V_1 - 1
orients all transitions weakly and the transition
	f23(a, b, c) -> f28(a, b, d) [ 0 >= a /\ 0 >= e + 1 ]
strictly and produces the following problem:
5:	T:
		(1, 1)    f0(a, b, c) -> f8(0, b, c)
		(?, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a /\ 0 >= d ]
		(?, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a ]
		(1, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a /\ 0 >= e + 1 ]
		(1, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a ]
		(1, 1)    f23(a, b, c) -> f23(a + 1, b, c) [ 0 >= a ]
		(?, 1)    f28(a, b, c) -> f23(a + 1, b, c)
		(?, 1)    f28(a, b, c) -> f23(a + 1, b, c) [ 0 >= d + 1 ]
		(?, 1)    f8(a, b, c) -> f8(a + 1, a, c) [ 0 >= a ]
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c)
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c) [ 0 >= d + 1 ]
		(1, 1)    f8(a, b, c) -> f23(0, b, c) [ a >= 1 ]
	start location:	f0
	leaf cost:	1

Repeatedly propagating knowledge in problem 5 produces the following problem:
6:	T:
		(1, 1)    f0(a, b, c) -> f8(0, b, c)
		(?, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a /\ 0 >= d ]
		(?, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a ]
		(1, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a /\ 0 >= e + 1 ]
		(1, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a ]
		(1, 1)    f23(a, b, c) -> f23(a + 1, b, c) [ 0 >= a ]
		(2, 1)    f28(a, b, c) -> f23(a + 1, b, c)
		(2, 1)    f28(a, b, c) -> f23(a + 1, b, c) [ 0 >= d + 1 ]
		(?, 1)    f8(a, b, c) -> f8(a + 1, a, c) [ 0 >= a ]
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c)
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c) [ 0 >= d + 1 ]
		(1, 1)    f8(a, b, c) -> f23(0, b, c) [ a >= 1 ]
	start location:	f0
	leaf cost:	1

A polynomial rank function with
	Pol(f8) = -3*V_1 + 1
	Pol(f14) = -3*V_1 - 1
and size complexities
	S("f8(a, b, c) -> f23(0, b, c) [ a >= 1 ]", 0-0) = 0
	S("f8(a, b, c) -> f23(0, b, c) [ a >= 1 ]", 0-1) = ?
	S("f8(a, b, c) -> f23(0, b, c) [ a >= 1 ]", 0-2) = c
	S("f14(a, b, c) -> f8(a + 1, b, c) [ 0 >= d + 1 ]", 0-0) = ?
	S("f14(a, b, c) -> f8(a + 1, b, c) [ 0 >= d + 1 ]", 0-1) = ?
	S("f14(a, b, c) -> f8(a + 1, b, c) [ 0 >= d + 1 ]", 0-2) = c
	S("f14(a, b, c) -> f8(a + 1, b, c)", 0-0) = ?
	S("f14(a, b, c) -> f8(a + 1, b, c)", 0-1) = ?
	S("f14(a, b, c) -> f8(a + 1, b, c)", 0-2) = c
	S("f8(a, b, c) -> f8(a + 1, a, c) [ 0 >= a ]", 0-0) = ?
	S("f8(a, b, c) -> f8(a + 1, a, c) [ 0 >= a ]", 0-1) = ?
	S("f8(a, b, c) -> f8(a + 1, a, c) [ 0 >= a ]", 0-2) = c
	S("f28(a, b, c) -> f23(a + 1, b, c) [ 0 >= d + 1 ]", 0-0) = 5
	S("f28(a, b, c) -> f23(a + 1, b, c) [ 0 >= d + 1 ]", 0-1) = ?
	S("f28(a, b, c) -> f23(a + 1, b, c) [ 0 >= d + 1 ]", 0-2) = ?
	S("f28(a, b, c) -> f23(a + 1, b, c)", 0-0) = 5
	S("f28(a, b, c) -> f23(a + 1, b, c)", 0-1) = ?
	S("f28(a, b, c) -> f23(a + 1, b, c)", 0-2) = ?
	S("f23(a, b, c) -> f23(a + 1, b, c) [ 0 >= a ]", 0-0) = 5
	S("f23(a, b, c) -> f23(a + 1, b, c) [ 0 >= a ]", 0-1) = ?
	S("f23(a, b, c) -> f23(a + 1, b, c) [ 0 >= a ]", 0-2) = ?
	S("f23(a, b, c) -> f28(a, b, d) [ 0 >= a ]", 0-0) = 5
	S("f23(a, b, c) -> f28(a, b, d) [ 0 >= a ]", 0-1) = ?
	S("f23(a, b, c) -> f28(a, b, d) [ 0 >= a ]", 0-2) = ?
	S("f23(a, b, c) -> f28(a, b, d) [ 0 >= a /\\ 0 >= e + 1 ]", 0-0) = 5
	S("f23(a, b, c) -> f28(a, b, d) [ 0 >= a /\\ 0 >= e + 1 ]", 0-1) = ?
	S("f23(a, b, c) -> f28(a, b, d) [ 0 >= a /\\ 0 >= e + 1 ]", 0-2) = ?
	S("f8(a, b, c) -> f14(a, a, c) [ 0 >= a ]", 0-0) = ?
	S("f8(a, b, c) -> f14(a, a, c) [ 0 >= a ]", 0-1) = ?
	S("f8(a, b, c) -> f14(a, a, c) [ 0 >= a ]", 0-2) = c
	S("f8(a, b, c) -> f14(a, a, c) [ 0 >= a /\\ 0 >= d ]", 0-0) = ?
	S("f8(a, b, c) -> f14(a, a, c) [ 0 >= a /\\ 0 >= d ]", 0-1) = ?
	S("f8(a, b, c) -> f14(a, a, c) [ 0 >= a /\\ 0 >= d ]", 0-2) = c
	S("f0(a, b, c) -> f8(0, b, c)", 0-0) = 0
	S("f0(a, b, c) -> f8(0, b, c)", 0-1) = b
	S("f0(a, b, c) -> f8(0, b, c)", 0-2) = c
orients the transitions
	f8(a, b, c) -> f8(a + 1, a, c) [ 0 >= a ]
	f8(a, b, c) -> f14(a, a, c) [ 0 >= a /\ 0 >= d ]
	f8(a, b, c) -> f14(a, a, c) [ 0 >= a ]
	f14(a, b, c) -> f8(a + 1, b, c) [ 0 >= d + 1 ]
	f14(a, b, c) -> f8(a + 1, b, c)
weakly and the transitions
	f8(a, b, c) -> f8(a + 1, a, c) [ 0 >= a ]
	f8(a, b, c) -> f14(a, a, c) [ 0 >= a /\ 0 >= d ]
	f8(a, b, c) -> f14(a, a, c) [ 0 >= a ]
strictly and produces the following problem:
7:	T:
		(1, 1)    f0(a, b, c) -> f8(0, b, c)
		(1, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a /\ 0 >= d ]
		(1, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a ]
		(1, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a /\ 0 >= e + 1 ]
		(1, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a ]
		(1, 1)    f23(a, b, c) -> f23(a + 1, b, c) [ 0 >= a ]
		(2, 1)    f28(a, b, c) -> f23(a + 1, b, c)
		(2, 1)    f28(a, b, c) -> f23(a + 1, b, c) [ 0 >= d + 1 ]
		(1, 1)    f8(a, b, c) -> f8(a + 1, a, c) [ 0 >= a ]
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c)
		(?, 1)    f14(a, b, c) -> f8(a + 1, b, c) [ 0 >= d + 1 ]
		(1, 1)    f8(a, b, c) -> f23(0, b, c) [ a >= 1 ]
	start location:	f0
	leaf cost:	1

Repeatedly propagating knowledge in problem 7 produces the following problem:
8:	T:
		(1, 1)    f0(a, b, c) -> f8(0, b, c)
		(1, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a /\ 0 >= d ]
		(1, 1)    f8(a, b, c) -> f14(a, a, c) [ 0 >= a ]
		(1, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a /\ 0 >= e + 1 ]
		(1, 1)    f23(a, b, c) -> f28(a, b, d) [ 0 >= a ]
		(1, 1)    f23(a, b, c) -> f23(a + 1, b, c) [ 0 >= a ]
		(2, 1)    f28(a, b, c) -> f23(a + 1, b, c)
		(2, 1)    f28(a, b, c) -> f23(a + 1, b, c) [ 0 >= d + 1 ]
		(1, 1)    f8(a, b, c) -> f8(a + 1, a, c) [ 0 >= a ]
		(2, 1)    f14(a, b, c) -> f8(a + 1, b, c)
		(2, 1)    f14(a, b, c) -> f8(a + 1, b, c) [ 0 >= d + 1 ]
		(1, 1)    f8(a, b, c) -> f23(0, b, c) [ a >= 1 ]
	start location:	f0
	leaf cost:	1

Complexity upper bound 17

Time: 0.412 sec (SMT: 0.388 sec)