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 12: f3 -> f4 : arg1'=arg1P_13, arg2'=arg2P_13, [ arg1>=2 && arg1==arg1P_13 && arg2==arg2P_13 ], cost: 1 14: f3 -> f12 : arg1'=arg1P_15, arg2'=arg2P_15, [ arg1<2 && arg1==arg1P_15 && arg2==arg2P_15 ], cost: 1 2: f4 -> f5 : arg1'=arg1P_3, arg2'=arg2P_3, [ arg1P_3==-1+arg1 && arg2==arg2P_3 ], cost: 1 3: f5 -> f6 : arg1'=arg1P_4, arg2'=arg2P_4, [ arg2P_4==arg2+arg1 && arg1==arg1P_4 ], cost: 1 5: f6 -> f7 : arg1'=arg1P_6, arg2'=arg2P_6, [ arg2>=arg1 && x12_1<0 && arg1==arg1P_6 && arg2==arg2P_6 ], cost: 1 6: f6 -> f7 : arg1'=arg1P_7, arg2'=arg2P_7, [ arg2>=arg1 && x36_1>0 && arg1==arg1P_7 && arg2==arg2P_7 ], cost: 1 8: f6 -> f9 : arg1'=arg1P_9, arg2'=arg2P_9, [ arg2 f9 : arg1'=arg1P_10, arg2'=arg2P_10, [ x39_1==0 && arg1==arg1P_10 && arg2==arg2P_10 ], cost: 1 4: f7 -> f8 : arg1'=arg1P_5, arg2'=arg2P_5, [ arg2P_5==-1+arg2 && arg1==arg1P_5 ], cost: 1 7: f8 -> f6 : arg1'=arg1P_8, arg2'=arg2P_8, [ arg1==arg1P_8 && arg2==arg2P_8 ], cost: 1 10: f9 -> f10 : arg1'=arg1P_11, arg2'=arg2P_11, [ arg1P_11==-1+arg1 && arg2==arg2P_11 ], cost: 1 11: f10 -> f11 : arg1'=arg1P_12, arg2'=arg2P_12, [ arg2P_12==arg2-arg1 && arg1==arg1P_12 ], cost: 1 13: f11 -> f3 : arg1'=arg1P_14, arg2'=arg2P_14, [ arg1==arg1P_14 && arg2==arg2P_14 ], cost: 1 15: __init -> f1 : arg1'=arg1P_16, arg2'=arg2P_16, [], cost: 1 Checking for constant complexity: The following rule is satisfiable with cost >= 1, yielding constant complexity: 15: __init -> f1 : arg1'=arg1P_16, arg2'=arg2P_16, [], 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 12: f3 -> f4 : arg1'=arg1P_13, arg2'=arg2P_13, [ arg1>=2 && arg1==arg1P_13 && arg2==arg2P_13 ], cost: 1 2: f4 -> f5 : arg1'=arg1P_3, arg2'=arg2P_3, [ arg1P_3==-1+arg1 && arg2==arg2P_3 ], cost: 1 3: f5 -> f6 : arg1'=arg1P_4, arg2'=arg2P_4, [ arg2P_4==arg2+arg1 && arg1==arg1P_4 ], cost: 1 5: f6 -> f7 : arg1'=arg1P_6, arg2'=arg2P_6, [ arg2>=arg1 && x12_1<0 && arg1==arg1P_6 && arg2==arg2P_6 ], cost: 1 6: f6 -> f7 : arg1'=arg1P_7, arg2'=arg2P_7, [ arg2>=arg1 && x36_1>0 && arg1==arg1P_7 && arg2==arg2P_7 ], cost: 1 8: f6 -> f9 : arg1'=arg1P_9, arg2'=arg2P_9, [ arg2 f9 : arg1'=arg1P_10, arg2'=arg2P_10, [ x39_1==0 && arg1==arg1P_10 && arg2==arg2P_10 ], cost: 1 4: f7 -> f8 : arg1'=arg1P_5, arg2'=arg2P_5, [ arg2P_5==-1+arg2 && arg1==arg1P_5 ], cost: 1 7: f8 -> f6 : arg1'=arg1P_8, arg2'=arg2P_8, [ arg1==arg1P_8 && arg2==arg2P_8 ], cost: 1 10: f9 -> f10 : arg1'=arg1P_11, arg2'=arg2P_11, [ arg1P_11==-1+arg1 && arg2==arg2P_11 ], cost: 1 11: f10 -> f11 : arg1'=arg1P_12, arg2'=arg2P_12, [ arg2P_12==arg2-arg1 && arg1==arg1P_12 ], cost: 1 13: f11 -> f3 : arg1'=arg1P_14, arg2'=arg2P_14, [ arg1==arg1P_14 && arg2==arg2P_14 ], cost: 1 15: __init -> f1 : arg1'=arg1P_16, arg2'=arg2P_16, [], 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 12: f3 -> f4 : [ arg1>=2 ], cost: 1 2: f4 -> f5 : arg1'=-1+arg1, [], cost: 1 3: f5 -> f6 : arg2'=arg2+arg1, [], cost: 1 6: f6 -> f7 : [ arg2>=arg1 ], cost: 1 8: f6 -> f9 : [ arg2 f9 : [], cost: 1 4: f7 -> f8 : arg2'=-1+arg2, [], cost: 1 7: f8 -> f6 : [], cost: 1 10: f9 -> f10 : arg1'=-1+arg1, [], cost: 1 11: f10 -> f11 : arg2'=arg2-arg1, [], cost: 1 13: f11 -> f3 : [], cost: 1 15: __init -> f1 : arg1'=arg1P_16, arg2'=arg2P_16, [], cost: 1 ### Simplification by acceleration and chaining ### Eliminated locations (on linear paths): Start location: __init 19: f3 -> f6 : arg1'=-1+arg1, arg2'=-1+arg2+arg1, [ arg1>=2 ], cost: 3 8: f6 -> f9 : [ arg2 f9 : [], cost: 1 21: f6 -> f6 : arg2'=-1+arg2, [ arg2>=arg1 ], cost: 3 23: f9 -> f3 : arg1'=-1+arg1, arg2'=1+arg2-arg1, [], cost: 3 17: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 Accelerating simple loops of location 5. Accelerating the following rules: 21: f6 -> f6 : arg2'=-1+arg2, [ arg2>=arg1 ], cost: 3 Accelerated rule 21 with backward acceleration, yielding the new rule 24. [accelerate] Nesting with 1 inner and 1 outer candidates Removing the simple loops: 21. Accelerated all simple loops using metering functions (where possible): Start location: __init 19: f3 -> f6 : arg1'=-1+arg1, arg2'=-1+arg2+arg1, [ arg1>=2 ], cost: 3 8: f6 -> f9 : [ arg2 f9 : [], cost: 1 24: f6 -> f6 : arg2'=-1+arg1, [ 1+arg2-arg1>=0 ], cost: 3+3*arg2-3*arg1 23: f9 -> f3 : arg1'=-1+arg1, arg2'=1+arg2-arg1, [], cost: 3 17: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 Chained accelerated rules (with incoming rules): Start location: __init 19: f3 -> f6 : arg1'=-1+arg1, arg2'=-1+arg2+arg1, [ arg1>=2 ], cost: 3 25: f3 -> f6 : arg1'=-1+arg1, arg2'=-2+arg1, [ arg1>=2 && 1+arg2>=0 ], cost: 6+3*arg2 8: f6 -> f9 : [ arg2 f9 : [], cost: 1 23: f9 -> f3 : arg1'=-1+arg1, arg2'=1+arg2-arg1, [], cost: 3 17: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 Eliminated locations (on tree-shaped paths): Start location: __init 26: f3 -> f9 : arg1'=-1+arg1, arg2'=-1+arg2+arg1, [ arg1>=2 && -1+arg2+arg1<-1+arg1 ], cost: 4 27: f3 -> f9 : arg1'=-1+arg1, arg2'=-1+arg2+arg1, [ arg1>=2 ], cost: 4 28: f3 -> f9 : arg1'=-1+arg1, arg2'=-2+arg1, [ arg1>=2 && 1+arg2>=0 ], cost: 7+3*arg2 29: f3 -> f9 : arg1'=-1+arg1, arg2'=-2+arg1, [ arg1>=2 && 1+arg2>=0 ], cost: 7+3*arg2 23: f9 -> f3 : arg1'=-1+arg1, arg2'=1+arg2-arg1, [], cost: 3 17: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 Merged rules: Start location: __init 30: f3 -> f9 : arg1'=-1+arg1, arg2'=-1+arg2+arg1, [ arg1>=2 ], cost: 4 31: f3 -> f9 : arg1'=-1+arg1, arg2'=-2+arg1, [ arg1>=2 && 1+arg2>=0 ], cost: 7+3*arg2 23: f9 -> f3 : arg1'=-1+arg1, arg2'=1+arg2-arg1, [], cost: 3 17: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 Eliminated locations (on tree-shaped paths): Start location: __init 32: f3 -> f3 : arg1'=-2+arg1, arg2'=1+arg2, [ arg1>=2 ], cost: 7 33: f3 -> f3 : arg1'=-2+arg1, arg2'=0, [ arg1>=2 && 1+arg2>=0 ], cost: 10+3*arg2 17: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 Accelerating simple loops of location 2. Accelerating the following rules: 32: f3 -> f3 : arg1'=-2+arg1, arg2'=1+arg2, [ arg1>=2 ], cost: 7 33: f3 -> f3 : arg1'=-2+arg1, arg2'=0, [ arg1>=2 && 1+arg2>=0 ], cost: 10+3*arg2 Accelerated rule 32 with backward acceleration, yielding the new rule 34. Accelerated rule 33 with backward acceleration, yielding the new rule 35. [accelerate] Nesting with 2 inner and 2 outer candidates Removing the simple loops: 32 33. Accelerated all simple loops using metering functions (where possible): Start location: __init 34: f3 -> f3 : arg1'=-2*k_1+arg1, arg2'=k_1+arg2, [ k_1>=0 && 2-2*k_1+arg1>=2 ], cost: 7*k_1 35: f3 -> f3 : arg1'=-2*k_2+arg1, arg2'=0, [ 1+arg2>=0 && k_2>=1 && 2-2*k_2+arg1>=2 ], cost: 10*k_2 17: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 Chained accelerated rules (with incoming rules): Start location: __init 17: __init -> f3 : arg1'=arg1P_1, arg2'=arg2P_2, [], cost: 3 36: __init -> f3 : arg1'=arg1P_1-2*k_1, arg2'=arg2P_2+k_1, [ k_1>=0 && 2+arg1P_1-2*k_1>=2 ], cost: 3+7*k_1 37: __init -> f3 : arg1'=arg1P_1-2*k_2, arg2'=0, [ k_2>=1 && 2+arg1P_1-2*k_2>=2 ], cost: 3+10*k_2 Removed unreachable locations (and leaf rules with constant cost): Start location: __init 36: __init -> f3 : arg1'=arg1P_1-2*k_1, arg2'=arg2P_2+k_1, [ k_1>=0 && 2+arg1P_1-2*k_1>=2 ], cost: 3+7*k_1 37: __init -> f3 : arg1'=arg1P_1-2*k_2, arg2'=0, [ k_2>=1 && 2+arg1P_1-2*k_2>=2 ], cost: 3+10*k_2 ### Computing asymptotic complexity ### Fully simplified ITS problem Start location: __init 36: __init -> f3 : arg1'=arg1P_1-2*k_1, arg2'=arg2P_2+k_1, [ k_1>=0 && 2+arg1P_1-2*k_1>=2 ], cost: 3+7*k_1 37: __init -> f3 : arg1'=arg1P_1-2*k_2, arg2'=0, [ k_2>=1 && 2+arg1P_1-2*k_2>=2 ], cost: 3+10*k_2 Computing asymptotic complexity for rule 36 Resulting cost 0 has complexity: Unknown Computing asymptotic complexity for rule 37 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),?)