NO Initial ITS Start location: l3 Program variables: p^0 0: l0 -> l1 : p^0'=p^post1, -p^post1+p^0 == 0, cost: 1 1: l1 -> l0 : p^0'=p^post2, p^0-p^post2 == 0, cost: 1 2: l2 -> l0 : p^0'=p^post3, (-1+p^2 == 0 /\ p^1 == 0 /\ p^post3 == 0), cost: 1 3: l3 -> l2 : p^0'=p^post4, -p^post4+p^0 == 0, cost: 1 Chained Linear Paths Start location: l3 Program variables: p^0 5: l0 -> l0 : p^0'=p^post2, (-p^post1+p^0 == 0 /\ p^post1-p^post2 == 0), cost: 1 4: l3 -> l0 : p^0'=p^post3, (-1+p^2 == 0 /\ p^1 == 0 /\ p^post3 == 0 /\ -p^post4+p^0 == 0), cost: 1 Eliminating location l2 by chaining: Applied chaining First rule: l3 -> l2 : p^0'=p^post4, -p^post4+p^0 == 0, cost: 1 Second rule: l2 -> l0 : p^0'=p^post3, (-1+p^2 == 0 /\ p^1 == 0 /\ p^post3 == 0), cost: 1 New rule: l3 -> l0 : p^0'=p^post3, (-1+p^2 == 0 /\ p^1 == 0 /\ p^post3 == 0 /\ -p^post4+p^0 == 0), cost: 1 Applied deletion Removed the following rules: 2 3 Eliminating location l1 by chaining: Applied chaining First rule: l0 -> l1 : p^0'=p^post1, -p^post1+p^0 == 0, cost: 1 Second rule: l1 -> l0 : p^0'=p^post2, p^0-p^post2 == 0, cost: 1 New rule: l0 -> l0 : p^0'=p^post2, (-p^post1+p^0 == 0 /\ p^post1-p^post2 == 0), cost: 1 Applied deletion Removed the following rules: 0 1 Simplified Transitions Start location: l3 Program variables: p^0 7: l0 -> l0 : T, cost: 1 6: l3 -> l0 : p^0'=0, T, cost: 1 Propagated Equalities Original rule: l3 -> l0 : p^0'=p^post3, (-1+p^2 == 0 /\ p^1 == 0 /\ p^post3 == 0 /\ -p^post4+p^0 == 0), cost: 1 New rule: l3 -> l0 : p^0'=0, (0 == 0 /\ -1+p^2 == 0 /\ p^1 == 0 /\ -p^post4+p^0 == 0), cost: 1 propagated equality p^post3 = 0 Propagated Equalities Original rule: l3 -> l0 : p^0'=0, (0 == 0 /\ -1+p^2 == 0 /\ p^1 == 0 /\ -p^post4+p^0 == 0), cost: 1 New rule: l3 -> l0 : p^0'=0, 0 == 0, cost: 1 propagated equality p^2 = 1 propagated equality p^1 = 0 propagated equality p^post4 = p^0 Simplified Guard Original rule: l3 -> l0 : p^0'=0, 0 == 0, cost: 1 New rule: l3 -> l0 : p^0'=0, T, cost: 1 Propagated Equalities Original rule: l0 -> l0 : p^0'=p^post2, (-p^post1+p^0 == 0 /\ p^post1-p^post2 == 0), cost: 1 New rule: l0 -> l0 : p^0'=p^post1, (0 == 0 /\ -p^post1+p^0 == 0), cost: 1 propagated equality p^post2 = p^post1 Propagated Equalities Original rule: l0 -> l0 : p^0'=p^post1, (0 == 0 /\ -p^post1+p^0 == 0), cost: 1 New rule: l0 -> l0 : p^0'=p^0, 0 == 0, cost: 1 propagated equality p^post1 = p^0 Simplified Guard Original rule: l0 -> l0 : p^0'=p^0, 0 == 0, cost: 1 New rule: l0 -> l0 : p^0'=p^0, T, cost: 1 Removed Trivial Updates Original rule: l0 -> l0 : p^0'=p^0, T, cost: 1 New rule: l0 -> l0 : T, cost: 1 Step with 6 Trace 6[T] Blocked [{}, {}] Step with 7 Trace 6[T], 7[T] Blocked [{}, {}, {}] Nonterm Start location: l3 Program variables: p^0 7: l0 -> l0 : T, cost: 1 8: l0 -> LoAT_sink : -1+n >= 0, cost: NONTERM 6: l3 -> l0 : p^0'=0, T, cost: 1 Certificate of Non-Termination Original rule: l0 -> l0 : T, cost: 1 New rule: l0 -> LoAT_sink : -1+n >= 0, cost: NONTERM Replacement map: {} Step with 8 Trace 6[T], 8[-1+n >= 0] Blocked [{}, {}, {8[T]}] Refute Counterexample [ p^0=0 ] 6 [ p^0=p^0 ] 8 NO Build SHA: a05f16bf13df659c382799650051f91bf6828c7b