WORST_CASE(Omega(1),?) ### Pre-processing the ITS problem ### Initial linear ITS problem Start location: l5 0: l0 -> l1 : x^0'=x^post_1, [ x^0<=0 && x^post_1==1 ], cost: 1 1: l0 -> l1 : x^0'=x^post_2, [ 1<=x^0 && x^post_2==1+x^0 ], cost: 1 4: l1 -> l2 : x^0'=x^post_5, [ x^0==x^post_5 ], cost: 1 2: l2 -> l3 : x^0'=x^post_3, [ 4<=x^0 && x^0==x^post_3 ], cost: 1 3: l2 -> l0 : x^0'=x^post_4, [ 1+x^0<=4 && x^0==x^post_4 ], cost: 1 5: l4 -> l1 : x^0'=x^post_6, [ x^1_1==5 && x^post_6==x^post_6 ], cost: 1 6: l5 -> l4 : x^0'=x^post_7, [ x^0==x^post_7 ], cost: 1 Checking for constant complexity: The following rule is satisfiable with cost >= 1, yielding constant complexity: 6: l5 -> l4 : x^0'=x^post_7, [ x^0==x^post_7 ], cost: 1 Removed unreachable and leaf rules: Start location: l5 0: l0 -> l1 : x^0'=x^post_1, [ x^0<=0 && x^post_1==1 ], cost: 1 1: l0 -> l1 : x^0'=x^post_2, [ 1<=x^0 && x^post_2==1+x^0 ], cost: 1 4: l1 -> l2 : x^0'=x^post_5, [ x^0==x^post_5 ], cost: 1 3: l2 -> l0 : x^0'=x^post_4, [ 1+x^0<=4 && x^0==x^post_4 ], cost: 1 5: l4 -> l1 : x^0'=x^post_6, [ x^1_1==5 && x^post_6==x^post_6 ], cost: 1 6: l5 -> l4 : x^0'=x^post_7, [ x^0==x^post_7 ], cost: 1 Simplified all rules, resulting in: Start location: l5 0: l0 -> l1 : x^0'=1, [ x^0<=0 ], cost: 1 1: l0 -> l1 : x^0'=1+x^0, [ 1<=x^0 ], cost: 1 4: l1 -> l2 : [], cost: 1 3: l2 -> l0 : [ 1+x^0<=4 ], cost: 1 5: l4 -> l1 : x^0'=x^post_6, [], cost: 1 6: l5 -> l4 : [], cost: 1 ### Simplification by acceleration and chaining ### Eliminated locations (on linear paths): Start location: l5 0: l0 -> l1 : x^0'=1, [ x^0<=0 ], cost: 1 1: l0 -> l1 : x^0'=1+x^0, [ 1<=x^0 ], cost: 1 8: l1 -> l0 : [ 1+x^0<=4 ], cost: 2 7: l5 -> l1 : x^0'=x^post_6, [], cost: 2 Eliminated locations (on tree-shaped paths): Start location: l5 9: l1 -> l1 : x^0'=1, [ x^0<=0 ], cost: 3 10: l1 -> l1 : x^0'=1+x^0, [ 1+x^0<=4 && 1<=x^0 ], cost: 3 7: l5 -> l1 : x^0'=x^post_6, [], cost: 2 Accelerating simple loops of location 1. Accelerating the following rules: 9: l1 -> l1 : x^0'=1, [ x^0<=0 ], cost: 3 10: l1 -> l1 : x^0'=1+x^0, [ 1+x^0<=4 && 1<=x^0 ], cost: 3 Failed to prove monotonicity of the guard of rule 9. Accelerated rule 10 with backward acceleration, yielding the new rule 11. [accelerate] Nesting with 2 inner and 2 outer candidates Removing the simple loops: 10. Accelerated all simple loops using metering functions (where possible): Start location: l5 9: l1 -> l1 : x^0'=1, [ x^0<=0 ], cost: 3 11: l1 -> l1 : x^0'=4, [ 1<=x^0 && 4-x^0>=0 ], cost: 12-3*x^0 7: l5 -> l1 : x^0'=x^post_6, [], cost: 2 Chained accelerated rules (with incoming rules): Start location: l5 7: l5 -> l1 : x^0'=x^post_6, [], cost: 2 12: l5 -> l1 : x^0'=1, [], cost: 5 13: l5 -> l1 : x^0'=4, [ 1<=x^post_6 && 4-x^post_6>=0 ], cost: 14-3*x^post_6 Removed unreachable locations (and leaf rules with constant cost): Start location: l5 13: l5 -> l1 : x^0'=4, [ 1<=x^post_6 && 4-x^post_6>=0 ], cost: 14-3*x^post_6 ### Computing asymptotic complexity ### Fully simplified ITS problem Start location: l5 13: l5 -> l1 : x^0'=4, [ 1<=x^post_6 && 4-x^post_6>=0 ], cost: 14-3*x^post_6 Computing asymptotic complexity for rule 13 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: [ x^0==x^post_7 ] WORST_CASE(Omega(1),?)