WORST_CASE(Omega(1),?) ### Pre-processing the ITS problem ### Initial linear ITS problem Start location: __init 0: f1 -> f2 : arg1'=arg1P_1, arg2'=arg2P_1, [ arg2==arg2P_1 ], cost: 1 1: f2 -> f3 : arg1'=arg1P_2, arg2'=arg2P_2, [ arg1==arg1P_2 ], cost: 1 9: f3 -> f4 : arg1'=arg1P_10, arg2'=arg2P_10, [ arg1>=0 && arg2>0 && arg1==arg1P_10 && arg2==arg2P_10 ], cost: 1 11: f3 -> f10 : arg1'=arg1P_12, arg2'=arg2P_12, [ arg1<0 && arg1==arg1P_12 && arg2==arg2P_12 ], cost: 1 12: f3 -> f10 : arg1'=arg1P_13, arg2'=arg2P_13, [ arg2<=0 && arg1==arg1P_13 && arg2==arg2P_13 ], cost: 1 2: f4 -> f5 : arg1'=arg1P_3, arg2'=arg2P_3, [ arg1==arg1P_3 && 1==arg2P_3 ], cost: 1 4: f5 -> f6 : arg1'=arg1P_5, arg2'=arg2P_5, [ arg1>arg2 && arg2>0 && arg1==arg1P_5 && arg2==arg2P_5 ], cost: 1 6: f5 -> f8 : arg1'=arg1P_7, arg2'=arg2P_7, [ arg1<=arg2 && arg1==arg1P_7 && arg2==arg2P_7 ], cost: 1 7: f5 -> f8 : arg1'=arg1P_8, arg2'=arg2P_8, [ arg2<=0 && arg1==arg1P_8 && arg2==arg2P_8 ], cost: 1 3: f6 -> f7 : arg1'=arg1P_4, arg2'=arg2P_4, [ arg2P_4==2*arg2 && arg1==arg1P_4 ], cost: 1 5: f7 -> f5 : arg1'=arg1P_6, arg2'=arg2P_6, [ arg1==arg1P_6 && arg2==arg2P_6 ], cost: 1 8: f8 -> f9 : arg1'=arg1P_9, arg2'=arg2P_9, [ arg1P_9==-1+arg1 && arg2==arg2P_9 ], cost: 1 10: f9 -> f3 : arg1'=arg1P_11, arg2'=arg2P_11, [ arg1==arg1P_11 && arg2==arg2P_11 ], cost: 1 13: __init -> f1 : arg1'=arg1P_14, arg2'=arg2P_14, [], cost: 1 Checking for constant complexity: The following rule is satisfiable with cost >= 1, yielding constant complexity: 13: __init -> f1 : arg1'=arg1P_14, arg2'=arg2P_14, [], cost: 1 Removed unreachable and leaf rules: Start location: __init 0: f1 -> f2 : arg1'=arg1P_1, arg2'=arg2P_1, [ arg2==arg2P_1 ], cost: 1 1: f2 -> f3 : arg1'=arg1P_2, arg2'=arg2P_2, [ arg1==arg1P_2 ], cost: 1 9: f3 -> f4 : arg1'=arg1P_10, arg2'=arg2P_10, [ arg1>=0 && arg2>0 && arg1==arg1P_10 && arg2==arg2P_10 ], cost: 1 2: f4 -> f5 : arg1'=arg1P_3, arg2'=arg2P_3, [ arg1==arg1P_3 && 1==arg2P_3 ], cost: 1 4: f5 -> f6 : arg1'=arg1P_5, arg2'=arg2P_5, [ arg1>arg2 && arg2>0 && arg1==arg1P_5 && arg2==arg2P_5 ], cost: 1 6: f5 -> f8 : arg1'=arg1P_7, arg2'=arg2P_7, [ arg1<=arg2 && arg1==arg1P_7 && arg2==arg2P_7 ], cost: 1 7: f5 -> f8 : arg1'=arg1P_8, arg2'=arg2P_8, [ arg2<=0 && arg1==arg1P_8 && arg2==arg2P_8 ], cost: 1 3: f6 -> f7 : arg1'=arg1P_4, arg2'=arg2P_4, [ arg2P_4==2*arg2 && arg1==arg1P_4 ], cost: 1 5: f7 -> f5 : arg1'=arg1P_6, arg2'=arg2P_6, [ arg1==arg1P_6 && arg2==arg2P_6 ], cost: 1 8: f8 -> f9 : arg1'=arg1P_9, arg2'=arg2P_9, [ arg1P_9==-1+arg1 && arg2==arg2P_9 ], cost: 1 10: f9 -> f3 : arg1'=arg1P_11, arg2'=arg2P_11, [ arg1==arg1P_11 && arg2==arg2P_11 ], cost: 1 13: __init -> f1 : arg1'=arg1P_14, arg2'=arg2P_14, [], cost: 1 Simplified all rules, resulting in: Start location: __init 0: f1 -> f2 : arg1'=arg1P_1, [], cost: 1 1: f2 -> f3 : arg2'=arg2P_2, [], cost: 1 9: f3 -> f4 : [ arg1>=0 && arg2>0 ], cost: 1 2: f4 -> f5 : arg2'=1, [], cost: 1 4: f5 -> f6 : [ arg1>arg2 && arg2>0 ], cost: 1 6: f5 -> f8 : [ arg1<=arg2 ], cost: 1 7: f5 -> f8 : [ arg2<=0 ], cost: 1 3: f6 -> f7 : arg2'=2*arg2, [], cost: 1 5: f7 -> f5 : [], cost: 1 8: f8 -> f9 : arg1'=-1+arg1, [], cost: 1 10: f9 -> f3 : [], cost: 1 13: __init -> f1 : arg1'=arg1P_14, arg2'=arg2P_14, [], cost: 1 ### Simplification by acceleration and chaining ### Eliminated locations (on linear paths): Start location: __init 16: f3 -> f5 : arg2'=1, [ arg1>=0 && arg2>0 ], cost: 2 6: f5 -> f8 : [ arg1<=arg2 ], cost: 1 7: f5 -> f8 : [ arg2<=0 ], cost: 1 18: f5 -> f5 : arg2'=2*arg2, [ arg1>arg2 && arg2>0 ], cost: 3 19: f8 -> f3 : arg1'=-1+arg1, [], cost: 2 15: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 Accelerating simple loops of location 4. Accelerating the following rules: 18: f5 -> f5 : arg2'=2*arg2, [ arg1>arg2 && arg2>0 ], cost: 3 Accelerated rule 18 with backward acceleration, yielding the new rule 20. [accelerate] Nesting with 1 inner and 1 outer candidates Removing the simple loops: 18. Accelerated all simple loops using metering functions (where possible): Start location: __init 16: f3 -> f5 : arg2'=1, [ arg1>=0 && arg2>0 ], cost: 2 6: f5 -> f8 : [ arg1<=arg2 ], cost: 1 7: f5 -> f8 : [ arg2<=0 ], cost: 1 20: f5 -> f5 : arg2'=arg2*2^k, [ arg2>0 && k>=0 && arg1>arg2*2^(-1+k) ], cost: 3*k 19: f8 -> f3 : arg1'=-1+arg1, [], cost: 2 15: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 Chained accelerated rules (with incoming rules): Start location: __init 16: f3 -> f5 : arg2'=1, [ arg1>=0 && arg2>0 ], cost: 2 21: f3 -> f5 : arg2'=2^k, [ arg1>=0 && arg2>0 && k>=0 && arg1>2^(-1+k) ], cost: 2+3*k 6: f5 -> f8 : [ arg1<=arg2 ], cost: 1 7: f5 -> f8 : [ arg2<=0 ], cost: 1 19: f8 -> f3 : arg1'=-1+arg1, [], cost: 2 15: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 Eliminated locations (on tree-shaped paths): Start location: __init 22: f3 -> f8 : arg2'=1, [ arg1>=0 && arg2>0 && arg1<=1 ], cost: 3 23: f3 -> f8 : arg2'=2^k, [ arg1>=0 && arg2>0 && k>=0 && arg1>2^(-1+k) && arg1<=2^k ], cost: 3+3*k 24: f3 -> f8 : arg2'=2^k, [ arg1>=0 && arg2>0 && k>=0 && arg1>2^(-1+k) && 2^k<=0 ], cost: 3+3*k 19: f8 -> f3 : arg1'=-1+arg1, [], cost: 2 15: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 Eliminated locations (on tree-shaped paths): Start location: __init 25: f3 -> f3 : arg1'=-1+arg1, arg2'=1, [ arg1>=0 && arg2>0 && arg1<=1 ], cost: 5 26: f3 -> f3 : arg1'=-1+arg1, arg2'=2^k, [ arg1>=0 && arg2>0 && k>=0 && arg1>2^(-1+k) && arg1<=2^k ], cost: 5+3*k 27: f3 -> f3 : arg1'=-1+arg1, arg2'=2^k, [ arg1>=0 && arg2>0 && k>=0 && arg1>2^(-1+k) && 2^k<=0 ], cost: 5+3*k 15: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 Accelerating simple loops of location 2. Accelerating the following rules: 25: f3 -> f3 : arg1'=-1+arg1, arg2'=1, [ arg1>=0 && arg2>0 && arg1<=1 ], cost: 5 26: f3 -> f3 : arg1'=-1+arg1, arg2'=2^k, [ arg1>=0 && arg2>0 && k>=0 && arg1>2^(-1+k) && arg1<=2^k ], cost: 5+3*k 27: f3 -> f3 : arg1'=-1+arg1, arg2'=2^k, [ arg1>=0 && arg2>0 && k>=0 && arg1>2^(-1+k) && 2^k<=0 ], cost: 5+3*k Accelerated rule 25 with backward acceleration, yielding the new rule 28. Failed to prove monotonicity of the guard of rule 26. Failed to prove monotonicity of the guard of rule 27. [accelerate] Nesting with 3 inner and 3 outer candidates Removing the simple loops: 25. Accelerated all simple loops using metering functions (where possible): Start location: __init 26: f3 -> f3 : arg1'=-1+arg1, arg2'=2^k, [ arg1>=0 && arg2>0 && k>=0 && arg1>2^(-1+k) && arg1<=2^k ], cost: 5+3*k 27: f3 -> f3 : arg1'=-1+arg1, arg2'=2^k, [ arg1>=0 && arg2>0 && k>=0 && arg1>2^(-1+k) && 2^k<=0 ], cost: 5+3*k 28: f3 -> f3 : arg1'=-1, arg2'=1, [ arg2>0 && arg1<=1 && 1+arg1>=1 ], cost: 5+5*arg1 15: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 Chained accelerated rules (with incoming rules): Start location: __init 15: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 29: __init -> f3 : arg1'=-1+arg1P_1, arg2'=2^k, [ arg1P_1>=0 && k>=0 && arg1P_1>2^(-1+k) && arg1P_1<=2^k ], cost: 8+3*k 30: __init -> f3 : arg1'=-1+arg1P_1, arg2'=2^k, [ arg1P_1>=0 && k>=0 && arg1P_1>2^(-1+k) && 2^k<=0 ], cost: 8+3*k 31: __init -> f3 : arg1'=-1, arg2'=1, [ arg1P_1<=1 && 1+arg1P_1>=1 ], cost: 8+5*arg1P_1 Removed unreachable locations (and leaf rules with constant cost): Start location: __init 29: __init -> f3 : arg1'=-1+arg1P_1, arg2'=2^k, [ arg1P_1>=0 && k>=0 && arg1P_1>2^(-1+k) && arg1P_1<=2^k ], cost: 8+3*k 30: __init -> f3 : arg1'=-1+arg1P_1, arg2'=2^k, [ arg1P_1>=0 && k>=0 && arg1P_1>2^(-1+k) && 2^k<=0 ], cost: 8+3*k 31: __init -> f3 : arg1'=-1, arg2'=1, [ arg1P_1<=1 && 1+arg1P_1>=1 ], cost: 8+5*arg1P_1 ### Computing asymptotic complexity ### Fully simplified ITS problem Start location: __init 29: __init -> f3 : arg1'=-1+arg1P_1, arg2'=2^k, [ arg1P_1>=0 && k>=0 && arg1P_1>2^(-1+k) && arg1P_1<=2^k ], cost: 8+3*k 30: __init -> f3 : arg1'=-1+arg1P_1, arg2'=2^k, [ arg1P_1>=0 && k>=0 && arg1P_1>2^(-1+k) && 2^k<=0 ], cost: 8+3*k 31: __init -> f3 : arg1'=-1, arg2'=1, [ arg1P_1<=1 && 1+arg1P_1>=1 ], cost: 8+5*arg1P_1 Computing asymptotic complexity for rule 31 Resulting cost 0 has complexity: Unknown Computing asymptotic complexity for rule 29 Resulting cost 0 has complexity: Unknown Computing asymptotic complexity for rule 30 Resulting cost 0 has complexity: Unknown Obtained the following overall complexity (w.r.t. the length of the input n): Complexity: Constant Cpx degree: 0 Solved cost: 1 Rule cost: 1 Rule guard: [] WORST_CASE(Omega(1),?)