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 && 23==arg2P_2 ], cost: 1 4: f3 -> f4 : arg1'=arg1P_5, arg2'=arg2P_5, [ arg1>=0 && arg1==arg1P_5 && arg2==arg2P_5 ], cost: 1 6: f3 -> f7 : arg1'=arg1P_7, arg2'=arg2P_7, [ arg1<0 && arg1==arg1P_7 && arg2==arg2P_7 ], cost: 1 2: f4 -> f5 : arg1'=arg1P_3, arg2'=arg2P_3, [ arg1P_3==-arg2+arg1 && arg2==arg2P_3 ], cost: 1 3: f5 -> f6 : arg1'=arg1P_4, arg2'=arg2P_4, [ arg2P_4==1+arg2 && arg1==arg1P_4 ], cost: 1 5: f6 -> f3 : arg1'=arg1P_6, arg2'=arg2P_6, [ arg1==arg1P_6 && arg2==arg2P_6 ], cost: 1 7: __init -> f1 : arg1'=arg1P_8, arg2'=arg2P_8, [], cost: 1 Checking for constant complexity: The following rule is satisfiable with cost >= 1, yielding constant complexity: 7: __init -> f1 : arg1'=arg1P_8, arg2'=arg2P_8, [], 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 && 23==arg2P_2 ], cost: 1 4: f3 -> f4 : arg1'=arg1P_5, arg2'=arg2P_5, [ arg1>=0 && arg1==arg1P_5 && arg2==arg2P_5 ], cost: 1 2: f4 -> f5 : arg1'=arg1P_3, arg2'=arg2P_3, [ arg1P_3==-arg2+arg1 && arg2==arg2P_3 ], cost: 1 3: f5 -> f6 : arg1'=arg1P_4, arg2'=arg2P_4, [ arg2P_4==1+arg2 && arg1==arg1P_4 ], cost: 1 5: f6 -> f3 : arg1'=arg1P_6, arg2'=arg2P_6, [ arg1==arg1P_6 && arg2==arg2P_6 ], cost: 1 7: __init -> f1 : arg1'=arg1P_8, arg2'=arg2P_8, [], cost: 1 Simplified all rules, resulting in: Start location: __init 0: f1 -> f2 : arg1'=arg1P_1, [], cost: 1 1: f2 -> f3 : arg2'=23, [], cost: 1 4: f3 -> f4 : [ arg1>=0 ], cost: 1 2: f4 -> f5 : arg1'=-arg2+arg1, [], cost: 1 3: f5 -> f6 : arg2'=1+arg2, [], cost: 1 5: f6 -> f3 : [], cost: 1 7: __init -> f1 : arg1'=arg1P_8, arg2'=arg2P_8, [], cost: 1 ### Simplification by acceleration and chaining ### Eliminated locations (on linear paths): Start location: __init 12: f3 -> f3 : arg1'=-arg2+arg1, arg2'=1+arg2, [ arg1>=0 ], cost: 4 9: __init -> f3 : arg1'=arg1P_1, arg2'=23, [], cost: 3 Accelerating simple loops of location 2. Accelerating the following rules: 12: f3 -> f3 : arg1'=-arg2+arg1, arg2'=1+arg2, [ arg1>=0 ], cost: 4 [test] deduced invariant -arg2<=0 Accelerated rule 12 with backward acceleration, yielding the new rule 13. [accelerate] Nesting with 1 inner and 1 outer candidates Accelerated all simple loops using metering functions (where possible): Start location: __init 12: f3 -> f3 : arg1'=-arg2+arg1, arg2'=1+arg2, [ arg1>=0 ], cost: 4 13: f3 -> f3 : arg1'=-1/2*k^2-arg2*k+1/2*k+arg1, arg2'=arg2+k, [ -arg2<=0 && k>=0 && -1/2-(-1+k)*arg2-1/2*(-1+k)^2+1/2*k+arg1>=0 ], cost: 4*k 9: __init -> f3 : arg1'=arg1P_1, arg2'=23, [], cost: 3 Chained accelerated rules (with incoming rules): Start location: __init 9: __init -> f3 : arg1'=arg1P_1, arg2'=23, [], cost: 3 14: __init -> f3 : arg1'=-23+arg1P_1, arg2'=24, [ arg1P_1>=0 ], cost: 7 15: __init -> f3 : arg1'=arg1P_1-1/2*k^2-45/2*k, arg2'=23+k, [ k>=0 && 45/2+arg1P_1-1/2*(-1+k)^2-45/2*k>=0 ], cost: 3+4*k Removed unreachable locations (and leaf rules with constant cost): Start location: __init 15: __init -> f3 : arg1'=arg1P_1-1/2*k^2-45/2*k, arg2'=23+k, [ k>=0 && 45/2+arg1P_1-1/2*(-1+k)^2-45/2*k>=0 ], cost: 3+4*k ### Computing asymptotic complexity ### Fully simplified ITS problem Start location: __init 15: __init -> f3 : arg1'=arg1P_1-1/2*k^2-45/2*k, arg2'=23+k, [ k>=0 && 45/2+arg1P_1-1/2*(-1+k)^2-45/2*k>=0 ], cost: 3+4*k Computing asymptotic complexity for rule 15 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),?)