unknown Initial ITS Start location: [1] Program variables: y 0: [1] -> [2] : y'=nondet, T, cost: 1 1: [2] -> [3] : y >= 0, cost: 1 4: [2] -> [5] : y < 0, cost: 1 2: [3] -> [4] : y'=-1+y, T, cost: 1 3: [4] -> [2] : T, cost: 1 Chained Linear Paths Start location: [1] Program variables: y 0: [1] -> [2] : y'=nondet, T, cost: 1 4: [2] -> [5] : y < 0, cost: 1 6: [2] -> [2] : y'=-1+y, y >= 0, cost: 1 Eliminating location [3] by chaining: Applied chaining First rule: [2] -> [3] : y >= 0, cost: 1 Second rule: [3] -> [4] : y'=-1+y, T, cost: 1 New rule: [2] -> [4] : y'=-1+y, y >= 0, cost: 1 Applied deletion Removed the following rules: 1 2 Eliminating location [4] by chaining: Applied chaining First rule: [2] -> [4] : y'=-1+y, y >= 0, cost: 1 Second rule: [4] -> [2] : T, cost: 1 New rule: [2] -> [2] : y'=-1+y, y >= 0, cost: 1 Applied deletion Removed the following rules: 3 5 Step with 0 Trace 0[T] Blocked [{}, {}] Step with 4 Trace 0[T], 4[(y < 0)] Blocked [{}, {}, {}] Backtrack Trace 0[T] Blocked [{}, {4[T]}] Step with 6 Trace 0[T], 6[(y >= 0)] Blocked [{}, {4[T]}, {}] Accelerate Start location: [1] Program variables: y 0: [1] -> [2] : y'=nondet, T, cost: 1 4: [2] -> [5] : y < 0, cost: 1 6: [2] -> [2] : y'=-1+y, y >= 0, cost: 1 7: [2] -> [2] : y'=-n+y, (-1+n >= 0 /\ 1-n+y >= 0), cost: 1 Loop Acceleration Original rule: [2] -> [2] : y'=-1+y, (y >= 0), cost: 1 New rule: [2] -> [2] : y'=-n+y, (-1+n >= 0 /\ 1-n+y >= 0), cost: 1 y >= 0 [0]: montonic decrease yields 1-n+y >= 0 y >= 0 [1]: eventual increase yields (1 <= 0 /\ y >= 0) Replacement map: {y >= 0 -> 1-n+y >= 0} Trace 0[T], 7[(-1+n >= 0 /\ 1-n+y >= 0)] Blocked [{}, {4[T]}, {6[T], 7[T]}] Step with 4 Trace 0[T], 7[(-1+n >= 0 /\ 1-n+y >= 0)], 4[(y < 0)] Blocked [{}, {4[T]}, {6[T], 7[T]}, {}] Backtrack Trace 0[T], 7[(-1+n >= 0 /\ 1-n+y >= 0)] Blocked [{}, {4[T]}, {4[T], 6[T], 7[T]}] Backtrack Trace 0[T] Blocked [{}, {4[T], 7[T]}] Step with 6 Trace 0[T], 6[(y >= 0)] Blocked [{}, {4[T], 7[T]}, {}] Covered Trace 0[T] Blocked [{}, {4[T], 6[T], 7[T]}] Backtrack Trace Blocked [{0[T]}] Accept unknown Build SHA: a05f16bf13df659c382799650051f91bf6828c7b