YES(?, a + 1000)

Initial complexity problem:
1:	T:
		(1, 1)    f0(a) -> f1(a)
		(?, 1)    f1(a) -> f1(a - 1000) [ a >= 1001 ]
	start location:	f0
	leaf cost:	0

A polynomial rank function with
	Pol(f0) = V_1 - 999
	Pol(f1) = V_1 - 999
orients all transitions weakly and the transition
	f1(a) -> f1(a - 1000) [ a >= 1001 ]
strictly and produces the following problem:
2:	T:
		(1, 1)          f0(a) -> f1(a)
		(a + 999, 1)    f1(a) -> f1(a - 1000) [ a >= 1001 ]
	start location:	f0
	leaf cost:	0

Complexity upper bound a + 1000

Time: 0.074 sec (SMT: 0.071 sec)