unknown Initial ITS Start location: [1] Program variables: x y 0: [1] -> [2] : x'=nondet, T, cost: 1 1: [2] -> [3] : y'=nondet1, T, cost: 1 2: [3] -> [4] : x >= 0, cost: 1 9: [3] -> [9] : x < 0, cost: 1 3: [4] -> [5] : x'=y+x, T, cost: 1 4: [5] -> [7] : y >= 0, cost: 1 7: [5] -> [6] : y < 0, cost: 1 8: [6] -> [3] : T, cost: 1 5: [7] -> [8] : y'=-1+y, T, cost: 1 6: [8] -> [6] : T, cost: 1 Chained Linear Paths Start location: [1] Program variables: x y 10: [1] -> [3] : x'=nondet, y'=nondet1, T, cost: 1 9: [3] -> [9] : x < 0, cost: 1 11: [3] -> [5] : x'=y+x, x >= 0, cost: 1 7: [5] -> [6] : y < 0, cost: 1 13: [5] -> [6] : y'=-1+y, y >= 0, cost: 1 8: [6] -> [3] : T, cost: 1 Eliminating location [2] by chaining: Applied chaining First rule: [1] -> [2] : x'=nondet, T, cost: 1 Second rule: [2] -> [3] : y'=nondet1, T, cost: 1 New rule: [1] -> [3] : x'=nondet, y'=nondet1, T, cost: 1 Applied deletion Removed the following rules: 0 1 Eliminating location [4] by chaining: Applied chaining First rule: [3] -> [4] : x >= 0, cost: 1 Second rule: [4] -> [5] : x'=y+x, T, cost: 1 New rule: [3] -> [5] : x'=y+x, x >= 0, cost: 1 Applied deletion Removed the following rules: 2 3 Eliminating location [7] by chaining: Applied chaining First rule: [5] -> [7] : y >= 0, cost: 1 Second rule: [7] -> [8] : y'=-1+y, T, cost: 1 New rule: [5] -> [8] : y'=-1+y, y >= 0, cost: 1 Applied deletion Removed the following rules: 4 5 Eliminating location [8] by chaining: Applied chaining First rule: [5] -> [8] : y'=-1+y, y >= 0, cost: 1 Second rule: [8] -> [6] : T, cost: 1 New rule: [5] -> [6] : y'=-1+y, y >= 0, cost: 1 Applied deletion Removed the following rules: 6 12 Step with 10 Trace 10[T] Blocked [{}, {}] Step with 9 Trace 10[T], 9[(x < 0)] Blocked [{}, {}, {}] Backtrack Trace 10[T] Blocked [{}, {9[T]}] Step with 11 Trace 10[T], 11[(x >= 0)] Blocked [{}, {9[T]}, {}] Step with 7 Trace 10[T], 11[(x >= 0)], 7[(y < 0)] Blocked [{}, {9[T]}, {}, {}] Step with 8 Trace 10[T], 11[(x >= 0)], 7[(y < 0)], 8[T] Blocked [{}, {9[T]}, {}, {}, {}] Accelerate Start location: [1] Program variables: x y 10: [1] -> [3] : x'=nondet, y'=nondet1, T, cost: 1 9: [3] -> [9] : x < 0, cost: 1 11: [3] -> [5] : x'=y+x, x >= 0, cost: 1 14: [3] -> [3] : x'=n*y+x, ((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0), cost: 1 7: [5] -> [6] : y < 0, cost: 1 13: [5] -> [6] : y'=-1+y, y >= 0, cost: 1 8: [6] -> [3] : T, cost: 1 Loop Acceleration Original rule: [3] -> [3] : x'=y+x, (y < 0 /\ x >= 0), cost: 1 New rule: [3] -> [3] : x'=n*y+x, ((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0), cost: 1 -y > 0 [0]: monotonic increase yields -y > 0 x >= 0 [0]: montonic decrease yields (-1+n)*y+x >= 0, dependencies: -y > 0 x >= 0 [1]: eventual increase yields (-y <= 0 /\ x >= 0), dependencies: -y > 0 Replacement map: {-y > 0 -> -y > 0, x >= 0 -> (-1+n)*y+x >= 0} Trace 10[T], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)] Blocked [{}, {9[T]}, {14[T]}] Step with 9 Trace 10[T], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)], 9[(x < 0)] Blocked [{}, {9[T]}, {14[T]}, {}] Backtrack Trace 10[T], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)] Blocked [{}, {9[T]}, {9[T], 14[T]}] Step with 11 Trace 10[T], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)], 11[(x >= 0)] Blocked [{}, {9[T]}, {9[T], 14[T]}, {}] Step with 7 Trace 10[T], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)], 11[(x >= 0)], 7[(y < 0)] Blocked [{}, {9[T]}, {9[T], 14[T]}, {}, {}] Step with 8 Trace 10[T], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)], 11[(x >= 0)], 7[(y < 0)], 8[T] Blocked [{}, {9[T]}, {9[T], 14[T]}, {}, {}, {}] Covered Trace 10[T], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)], 11[(x >= 0)], 7[(y < 0)] Blocked [{}, {9[T]}, {9[T], 14[T]}, {}, {8[T]}] Backtrack Trace 10[T], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)], 11[(x >= 0)] Blocked [{}, {9[T]}, {9[T], 14[T]}, {7[T]}] Backtrack Trace 10[T], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)] Blocked [{}, {9[T]}, {9[T], 11[T], 14[T]}] Backtrack Trace 10[T] Blocked [{}, {9[T], 14[T]}] Step with 11 Trace 10[T], 11[(x >= 0)] Blocked [{}, {9[T], 14[T]}, {}] Step with 7 Trace 10[T], 11[(x >= 0)], 7[(y < 0)] Blocked [{}, {9[T], 14[T]}, {}, {}] Step with 8 Trace 10[T], 11[(x >= 0)], 7[(y < 0)], 8[T] Blocked [{}, {9[T], 14[T]}, {}, {}, {}] Covered Trace 10[T], 11[(x >= 0)], 7[(y < 0)] Blocked [{}, {9[T], 14[T]}, {}, {8[T]}] Backtrack Trace 10[T], 11[(x >= 0)] Blocked [{}, {9[T], 14[T]}, {7[T]}] Step with 13 Trace 10[T], 11[(x >= 0)], 13[(y >= 0)] Blocked [{}, {9[T], 14[T]}, {7[T]}, {}] Step with 8 Trace 10[T], 11[(x >= 0)], 13[(y >= 0)], 8[T] Blocked [{}, {9[T], 14[T]}, {7[T]}, {}, {}] Accelerate Start location: [1] Program variables: x y 10: [1] -> [3] : x'=nondet, y'=nondet1, T, cost: 1 9: [3] -> [9] : x < 0, cost: 1 11: [3] -> [5] : x'=y+x, x >= 0, cost: 1 14: [3] -> [3] : x'=n*y+x, ((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0), cost: 1 15: [3] -> [3] : x'=-1/2*n2^2+y*n2+x+1/2*n2, y'=y-n2, (1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0), cost: 1 7: [5] -> [6] : y < 0, cost: 1 13: [5] -> [6] : y'=-1+y, y >= 0, cost: 1 8: [6] -> [3] : T, cost: 1 Loop Acceleration Original rule: [3] -> [3] : x'=y+x, y'=-1+y, (y >= 0 /\ x >= 0), cost: 1 New rule: [3] -> [3] : x'=-1/2*n2^2+y*n2+x+1/2*n2, y'=y-n2, (1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0), cost: 1 y >= 0 [0]: montonic decrease yields 1+y-n2 >= 0 y >= 0 [1]: eventual increase yields (1 <= 0 /\ y >= 0) x >= 0 [0]: monotonic increase yields x >= 0, dependencies: y >= 0 Replacement map: {y >= 0 -> 1+y-n2 >= 0, x >= 0 -> x >= 0} Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)] Blocked [{}, {9[T], 14[T]}, {15[T]}] Step with 11 Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 11[(x >= 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 15[T]}, {}] Step with 13 Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 11[(x >= 0)], 13[(y >= 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 15[T]}, {}, {}] Step with 8 Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 11[(x >= 0)], 13[(y >= 0)], 8[T] Blocked [{}, {9[T], 14[T]}, {9[T], 15[T]}, {}, {}, {}] Covered Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 11[(x >= 0)], 13[(y >= 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 15[T]}, {}, {8[T]}] Backtrack Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 11[(x >= 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 15[T]}, {13[T]}] Step with 7 Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 11[(x >= 0)], 7[(y < 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 15[T]}, {13[T]}, {}] Step with 8 Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 11[(x >= 0)], 7[(y < 0)], 8[T] Blocked [{}, {9[T], 14[T]}, {9[T], 15[T]}, {13[T]}, {}, {}] Covered Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 11[(x >= 0)], 7[(y < 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 15[T]}, {13[T]}, {8[T]}] Backtrack Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 11[(x >= 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 15[T]}, {7[T], 13[T]}] Backtrack Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 11[T], 15[T]}] Step with 14 Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 11[T], 15[T]}, {14[T]}] Acceleration Failed marked recursive suffix as redundant Step with 9 Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)], 9[(x < 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 11[T], 15[T]}, {14[T], 15[T]}, {}] Backtrack Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 11[T], 15[T]}, {9[T], 14[T], 15[T]}] Step with 11 Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)], 11[(x >= 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 11[T], 15[T]}, {9[T], 14[T], 15[T]}, {}] Step with 7 Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)], 11[(x >= 0)], 7[(y < 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 11[T], 15[T]}, {9[T], 14[T], 15[T]}, {}, {}] Step with 8 Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)], 11[(x >= 0)], 7[(y < 0)], 8[T] Blocked [{}, {9[T], 14[T]}, {9[T], 11[T], 15[T]}, {9[T], 14[T], 15[T]}, {}, {}, {}] Covered Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)], 11[(x >= 0)], 7[(y < 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 11[T], 15[T]}, {9[T], 14[T], 15[T]}, {}, {8[T]}] Backtrack Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)], 11[(x >= 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 11[T], 15[T]}, {9[T], 14[T], 15[T]}, {7[T]}] Backtrack Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)], 14[((-1+n)*y+x >= 0 /\ -1+n >= 0 /\ -y > 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 11[T], 15[T]}, {9[T], 11[T], 14[T], 15[T]}] Backtrack Trace 10[T], 15[(1+y-n2 >= 0 /\ -1+n2 >= 0 /\ x >= 0)] Blocked [{}, {9[T], 14[T]}, {9[T], 11[T], 14[T], 15[T]}] Backtrack Trace 10[T] Blocked [{}, {9[T], 14[T], 15[T]}] Step with 11 Trace 10[T], 11[(x >= 0)] Blocked [{}, {9[T], 14[T], 15[T]}, {}] Step with 7 Trace 10[T], 11[(x >= 0)], 7[(y < 0)] Blocked [{}, {9[T], 14[T], 15[T]}, {}, {}] Step with 8 Trace 10[T], 11[(x >= 0)], 7[(y < 0)], 8[T] Blocked [{}, {9[T], 14[T], 15[T]}, {}, {}, {}] Covered Trace 10[T], 11[(x >= 0)], 7[(y < 0)] Blocked [{}, {9[T], 14[T], 15[T]}, {}, {8[T]}] Backtrack Trace 10[T], 11[(x >= 0)] Blocked [{}, {9[T], 14[T], 15[T]}, {7[T]}] Step with 13 Trace 10[T], 11[(x >= 0)], 13[(y >= 0)] Blocked [{}, {9[T], 14[T], 15[T]}, {7[T]}, {}] Step with 8 Trace 10[T], 11[(x >= 0)], 13[(y >= 0)], 8[T] Blocked [{}, {9[T], 14[T], 15[T]}, {7[T]}, {}, {}] Covered Trace 10[T], 11[(x >= 0)], 13[(y >= 0)] Blocked [{}, {9[T], 14[T], 15[T]}, {7[T]}, {8[T]}] Backtrack Trace 10[T], 11[(x >= 0)] Blocked [{}, {9[T], 14[T], 15[T]}, {7[T], 13[T]}] Backtrack Trace 10[T] Blocked [{}, {9[T], 11[T], 14[T], 15[T]}] Backtrack Trace Blocked [{10[T]}] Accept unknown Build SHA: a05f16bf13df659c382799650051f91bf6828c7b