NO ### Pre-processing the ITS problem ### Initial linear ITS problem Start location: l3 0: l0 -> l1 : x^0'=x^post_1, y^0'=y^post_1, [ 1<=x^0 && x^0==x^post_1 && y^0==y^post_1 ], cost: 1 1: l1 -> l0 : x^0'=x^post_2, y^0'=y^post_2, [ y^post_2==-1+y^0 && x^post_2==x^post_2 ], cost: 1 2: l1 -> l0 : x^0'=x^post_3, y^0'=y^post_3, [ x^post_3==-1+x^0 && y^0==y^post_3 ], cost: 1 3: l2 -> l0 : x^0'=x^post_4, y^0'=y^post_4, [ x^0==x^post_4 && y^0==y^post_4 ], cost: 1 4: l3 -> l2 : x^0'=x^post_5, y^0'=y^post_5, [ x^0==x^post_5 && y^0==y^post_5 ], cost: 1 Checking for constant complexity: The following rule is satisfiable with cost >= 1, yielding constant complexity: 4: l3 -> l2 : x^0'=x^post_5, y^0'=y^post_5, [ x^0==x^post_5 && y^0==y^post_5 ], cost: 1 Simplified all rules, resulting in: Start location: l3 0: l0 -> l1 : [ 1<=x^0 ], cost: 1 1: l1 -> l0 : x^0'=x^post_2, y^0'=-1+y^0, [], cost: 1 2: l1 -> l0 : x^0'=-1+x^0, [], cost: 1 3: l2 -> l0 : [], cost: 1 4: l3 -> l2 : [], cost: 1 ### Simplification by acceleration and chaining ### Eliminated locations (on linear paths): Start location: l3 0: l0 -> l1 : [ 1<=x^0 ], cost: 1 1: l1 -> l0 : x^0'=x^post_2, y^0'=-1+y^0, [], cost: 1 2: l1 -> l0 : x^0'=-1+x^0, [], cost: 1 5: l3 -> l0 : [], cost: 2 Eliminated locations (on tree-shaped paths): Start location: l3 6: l0 -> l0 : x^0'=x^post_2, y^0'=-1+y^0, [ 1<=x^0 ], cost: 2 7: l0 -> l0 : x^0'=-1+x^0, [ 1<=x^0 ], cost: 2 5: l3 -> l0 : [], cost: 2 Accelerating simple loops of location 0. Accelerating the following rules: 6: l0 -> l0 : x^0'=x^post_2, y^0'=-1+y^0, [ 1<=x^0 ], cost: 2 7: l0 -> l0 : x^0'=-1+x^0, [ 1<=x^0 ], cost: 2 [test] deduced pseudo-invariant -x^post_2+x^0<=0, also trying x^post_2-x^0<=-1 Accelerated rule 6 with non-termination, yielding the new rule 8. Accelerated rule 6 with non-termination, yielding the new rule 9. Accelerated rule 6 with backward acceleration, yielding the new rule 10. Accelerated rule 7 with backward acceleration, yielding the new rule 11. [accelerate] Nesting with 1 inner and 2 outer candidates Removing the simple loops: 7. Also removing duplicate rules: 9. Accelerated all simple loops using metering functions (where possible): Start location: l3 6: l0 -> l0 : x^0'=x^post_2, y^0'=-1+y^0, [ 1<=x^0 ], cost: 2 8: l0 -> [4] : [ 1<=x^0 && 1<=x^post_2 ], cost: NONTERM 10: l0 -> [4] : [ 1<=x^0 && -x^post_2+x^0<=0 ], cost: NONTERM 11: l0 -> l0 : x^0'=0, [ x^0>=0 ], cost: 2*x^0 5: l3 -> l0 : [], cost: 2 Chained accelerated rules (with incoming rules): Start location: l3 5: l3 -> l0 : [], cost: 2 12: l3 -> l0 : x^0'=x^post_2, y^0'=-1+y^0, [ 1<=x^0 ], cost: 4 13: l3 -> [4] : [ 1<=x^0 ], cost: NONTERM 14: l3 -> [4] : [ 1<=x^0 ], cost: NONTERM 15: l3 -> l0 : x^0'=0, [ x^0>=0 ], cost: 2+2*x^0 Removed unreachable locations (and leaf rules with constant cost): Start location: l3 13: l3 -> [4] : [ 1<=x^0 ], cost: NONTERM 14: l3 -> [4] : [ 1<=x^0 ], cost: NONTERM 15: l3 -> l0 : x^0'=0, [ x^0>=0 ], cost: 2+2*x^0 ### Computing asymptotic complexity ### Fully simplified ITS problem Start location: l3 14: l3 -> [4] : [ 1<=x^0 ], cost: NONTERM 15: l3 -> l0 : x^0'=0, [ x^0>=0 ], cost: 2+2*x^0 Computing asymptotic complexity for rule 14 Guard is satisfiable, yielding nontermination Resulting cost NONTERM has complexity: Nonterm Found new complexity Nonterm. Obtained the following overall complexity (w.r.t. the length of the input n): Complexity: Nonterm Cpx degree: Nonterm Solved cost: NONTERM Rule cost: NONTERM Rule guard: [ 1<=x^0 ] NO