WORST_CASE(?, O(1)) Initial complexity problem: 1: T: (Comp: ?, Cost: 1) f8(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f8(Ar_0 - 1, Ar_1, Ar_2, Ar_3)) [ Ar_0 >= 0 ] (Comp: ?, Cost: 1) f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, Ar_1 - 1, Ar_2, Ar_3)) [ Ar_1 >= 0 ] (Comp: ?, Cost: 1) f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, Ar_2 - 1, Ar_3)) [ Ar_2 >= 0 ] (Comp: ?, Cost: 1) f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f36(Ar_0, Ar_1, Ar_2, Ar_3)) [ 0 >= Ar_2 + 1 ] (Comp: ?, Cost: 1) f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, 999, Ar_3)) [ 0 >= Ar_1 + 1 ] (Comp: ?, Cost: 1) f0(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, 999, Ar_2, 1)) (Comp: ?, Cost: 1) f8(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, 999, Ar_2, Ar_3)) [ 0 >= Ar_0 + 1 ] (Comp: 1, Cost: 0) koat_start(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f0(Ar_0, Ar_1, Ar_2, Ar_3)) [ 0 <= 0 ] start location: koat_start leaf cost: 0 Testing for reachability in the complexity graph removes the following transitions from problem 1: f8(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f8(Ar_0 - 1, Ar_1, Ar_2, Ar_3)) [ Ar_0 >= 0 ] f8(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, 999, Ar_2, Ar_3)) [ 0 >= Ar_0 + 1 ] We thus obtain the following problem: 2: T: (Comp: ?, Cost: 1) f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f36(Ar_0, Ar_1, Ar_2, Ar_3)) [ 0 >= Ar_2 + 1 ] (Comp: ?, Cost: 1) f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, Ar_2 - 1, Ar_3)) [ Ar_2 >= 0 ] (Comp: ?, Cost: 1) f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, 999, Ar_3)) [ 0 >= Ar_1 + 1 ] (Comp: ?, Cost: 1) f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, Ar_1 - 1, Ar_2, Ar_3)) [ Ar_1 >= 0 ] (Comp: ?, Cost: 1) f0(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, 999, Ar_2, 1)) (Comp: 1, Cost: 0) koat_start(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f0(Ar_0, Ar_1, Ar_2, Ar_3)) [ 0 <= 0 ] start location: koat_start leaf cost: 0 Repeatedly propagating knowledge in problem 2 produces the following problem: 3: T: (Comp: ?, Cost: 1) f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f36(Ar_0, Ar_1, Ar_2, Ar_3)) [ 0 >= Ar_2 + 1 ] (Comp: ?, Cost: 1) f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, Ar_2 - 1, Ar_3)) [ Ar_2 >= 0 ] (Comp: ?, Cost: 1) f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, 999, Ar_3)) [ 0 >= Ar_1 + 1 ] (Comp: ?, Cost: 1) f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, Ar_1 - 1, Ar_2, Ar_3)) [ Ar_1 >= 0 ] (Comp: 1, Cost: 1) f0(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, 999, Ar_2, 1)) (Comp: 1, Cost: 0) koat_start(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f0(Ar_0, Ar_1, Ar_2, Ar_3)) [ 0 <= 0 ] start location: koat_start leaf cost: 0 A polynomial rank function with Pol(f28) = 1 Pol(f36) = 0 Pol(f19) = 2 Pol(f0) = 2 Pol(koat_start) = 2 orients all transitions weakly and the transitions f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f36(Ar_0, Ar_1, Ar_2, Ar_3)) [ 0 >= Ar_2 + 1 ] f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, 999, Ar_3)) [ 0 >= Ar_1 + 1 ] strictly and produces the following problem: 4: T: (Comp: 2, Cost: 1) f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f36(Ar_0, Ar_1, Ar_2, Ar_3)) [ 0 >= Ar_2 + 1 ] (Comp: ?, Cost: 1) f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, Ar_2 - 1, Ar_3)) [ Ar_2 >= 0 ] (Comp: 2, Cost: 1) f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, 999, Ar_3)) [ 0 >= Ar_1 + 1 ] (Comp: ?, Cost: 1) f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, Ar_1 - 1, Ar_2, Ar_3)) [ Ar_1 >= 0 ] (Comp: 1, Cost: 1) f0(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, 999, Ar_2, 1)) (Comp: 1, Cost: 0) koat_start(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f0(Ar_0, Ar_1, Ar_2, Ar_3)) [ 0 <= 0 ] start location: koat_start leaf cost: 0 A polynomial rank function with Pol(f28) = V_3 + 1 Pol(f36) = V_3 + 1 Pol(f19) = 1000 Pol(f0) = 1000 Pol(koat_start) = 1000 orients all transitions weakly and the transition f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, Ar_2 - 1, Ar_3)) [ Ar_2 >= 0 ] strictly and produces the following problem: 5: T: (Comp: 2, Cost: 1) f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f36(Ar_0, Ar_1, Ar_2, Ar_3)) [ 0 >= Ar_2 + 1 ] (Comp: 1000, Cost: 1) f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, Ar_2 - 1, Ar_3)) [ Ar_2 >= 0 ] (Comp: 2, Cost: 1) f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, 999, Ar_3)) [ 0 >= Ar_1 + 1 ] (Comp: ?, Cost: 1) f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, Ar_1 - 1, Ar_2, Ar_3)) [ Ar_1 >= 0 ] (Comp: 1, Cost: 1) f0(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, 999, Ar_2, 1)) (Comp: 1, Cost: 0) koat_start(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f0(Ar_0, Ar_1, Ar_2, Ar_3)) [ 0 <= 0 ] start location: koat_start leaf cost: 0 A polynomial rank function with Pol(f28) = V_2 + 1 Pol(f36) = V_2 + 1 Pol(f19) = V_2 + 1 Pol(f0) = 1000 Pol(koat_start) = 1000 orients all transitions weakly and the transition f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, Ar_1 - 1, Ar_2, Ar_3)) [ Ar_1 >= 0 ] strictly and produces the following problem: 6: T: (Comp: 2, Cost: 1) f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f36(Ar_0, Ar_1, Ar_2, Ar_3)) [ 0 >= Ar_2 + 1 ] (Comp: 1000, Cost: 1) f28(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, Ar_2 - 1, Ar_3)) [ Ar_2 >= 0 ] (Comp: 2, Cost: 1) f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f28(Ar_0, Ar_1, 999, Ar_3)) [ 0 >= Ar_1 + 1 ] (Comp: 1000, Cost: 1) f19(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, Ar_1 - 1, Ar_2, Ar_3)) [ Ar_1 >= 0 ] (Comp: 1, Cost: 1) f0(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f19(Ar_0, 999, Ar_2, 1)) (Comp: 1, Cost: 0) koat_start(Ar_0, Ar_1, Ar_2, Ar_3) -> Com_1(f0(Ar_0, Ar_1, Ar_2, Ar_3)) [ 0 <= 0 ] start location: koat_start leaf cost: 0 Complexity upper bound 2005 Time: 0.836 sec (SMT: 0.808 sec)