/export/starexec/sandbox2/solver/bin/starexec_run_default /export/starexec/sandbox2/benchmark/theBenchmark.xml /export/starexec/sandbox2/output/output_files -------------------------------------------------------------------------------- NO ** BEGIN proof argument ** The following rule was generated while unfolding the analyzed TRS: [iteration = 3] f(g(_0),_0,g(g(_1))) -> f(g(g(_1)),g(_1),g(g(_1))) Let l be the left-hand side and r be the right-hand side of this rule. Let p = epsilon, theta1 = {} and theta2 = {_0->g(_1)}. We have r|p = f(g(g(_1)),g(_1),g(g(_1))) and theta2(theta1(l)) = theta1(r|p). Hence, the term theta1(l) = f(g(_0),_0,g(g(_1))) loops w.r.t. the analyzed TRS. ** END proof argument ** ** BEGIN proof description ** ## Searching for a generalized rewrite rule (a rule whose right-hand side contains a variable that does not occur in the left-hand side)... No generalized rewrite rule found! ## Applying the DP framework... ## 2 initial DP problems to solve. ## First, we try to decompose these problems into smaller problems. ## Round 1 [2 DP problems]: ## DP problem: Dependency pairs = [f^#(g(_0),_0,_1) -> f^#(_1,_1,g(_1))] TRS = {f(g(_0),_0,_1) -> f(_1,_1,g(_1)), g(g(_0)) -> g(_0)} ## Trying with homeomorphic embeddings... Failed! ## Trying with polynomial interpretations... Failed! ## Trying with lexicographic path orders... Failed! ## Trying with Knuth-Bendix orders... Failed! Don't know whether this DP problem is finite. ## DP problem: Dependency pairs = [g^#(g(_0)) -> g^#(_0)] TRS = {f(g(_0),_0,_1) -> f(_1,_1,g(_1)), g(g(_0)) -> g(_0)} ## Trying with homeomorphic embeddings... Success! This DP problem is finite. ## A DP problem could not be proved finite. ## Now, we try to prove that this problem is infinite. ## Trying to find a loop (forward=true, backward=false, max=-1) # max_depth=2, unfold_variables=false: # Iteration 0: no loop found, 1 unfolded rule generated. # Iteration 1: no loop found, 1 unfolded rule generated. # Iteration 2: no loop found, 2 unfolded rules generated. # Iteration 3: success, found a loop, 1 unfolded rule generated. Here is the successful unfolding. Let IR be the TRS under analysis. L0 = f^#(g(_0),_0,_1) -> f^#(_1,_1,g(_1)) [trans] is in U_IR^0. We build a unit triple from L0. ==> L1 = f^#(g(_0),_0,_1) -> f^#(_1,_1,g(_1)) [unit] is in U_IR^1. Let p1 = [2]. We unfold the rule of L1 forwards at position p1 with the rule g(g(_0)) -> g(_0). ==> L2 = f^#(g(_0),_0,g(_1)) -> f^#(g(_1),g(_1),g(_1)) [unit] is in U_IR^2. Let p2 = [1]. We unfold the rule of L2 forwards at position p2 with the rule g(g(_0)) -> g(_0). ==> L3 = f^#(g(_0),_0,g(g(_1))) -> f^#(g(g(_1)),g(_1),g(g(_1))) [unit] is in U_IR^3. This DP problem is infinite. Proof run on Linux version 3.10.0-1160.25.1.el7.x86_64 for amd64 using Java version 1.8.0_292 ** END proof description ** Total number of generated unfolded rules = 16