/export/starexec/sandbox/solver/bin/starexec_run_default /export/starexec/sandbox/benchmark/theBenchmark.xml /export/starexec/sandbox/output/output_files -------------------------------------------------------------------------------- NO ** BEGIN proof argument ** The following rule was generated while unfolding the analyzed TRS: [iteration = 6] f(u(d,h(d),_0),k(b),u(d,h(d),_0)) -> f(u(d,h(d),_0),k(b),u(d,h(d),_0)) Let l be the left-hand side and r be the right-hand side of this rule. Let p = epsilon, theta1 = {} and theta2 = {}. We have r|p = f(u(d,h(d),_0),k(b),u(d,h(d),_0)) and theta2(theta1(l)) = theta1(r|p). Hence, the term theta1(l) = f(u(d,h(d),_0),k(b),u(d,h(d),_0)) 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... ## 1 initial DP problem to solve. ## First, we try to decompose this problem into smaller problems. ## Round 1 [1 DP problem]: ## DP problem: Dependency pairs = [f^#(k(a),k(b),_0) -> f^#(_0,_0,_0)] TRS = {g(_0) -> u(h(_0),h(_0),_0), u(d,c(_0),_1) -> k(_0), h(d) -> c(a), h(d) -> c(b), f(k(a),k(b),_0) -> f(_0,_0,_0)} ## Trying with homeomorphic embeddings... Failed! ## Trying with polynomial interpretations... This DP problem is too complex! Aborting! ## Trying with lexicographic path orders... Failed! ## Trying with Knuth-Bendix orders... Failed! Don't know whether 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=true, max=20) # max_depth=20, 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: no loop found, 3 unfolded rules generated. # Iteration 4: no loop found, 2 unfolded rules generated. # Iteration 5: no loop found, 3 unfolded rules generated. # Iteration 6: success, found a loop, 2 unfolded rules generated. Here is the successful unfolding. Let IR be the TRS under analysis. L0 = f^#(k(a),k(b),_0) -> f^#(_0,_0,_0) [trans] is in U_IR^0. We build a unit triple from L0. ==> L1 = f^#(k(a),k(b),_0) -> f^#(_0,_0,_0) [unit] is in U_IR^1. Let p1 = [0]. We unfold the rule of L1 backwards at position p1 with the rule u(d,c(_0),_1) -> k(_0). ==> L2 = f^#(u(d,c(a),_0),k(b),_1) -> f^#(_1,_1,_1) [unit] is in U_IR^2. Let p2 = [0, 1]. We unfold the rule of L2 backwards at position p2 with the rule h(d) -> c(a). ==> L3 = f^#(u(d,h(d),_0),k(b),_1) -> f^#(_1,_1,_1) [unit] is in U_IR^3. Let p3 = [0]. The subterm at position p3 in the left-hand side of the rule of L3 unifies with the subterm at position p3 in the right-hand side of the rule of L3. ==> L4 = f^#(u(d,h(d),_0),k(b),u(d,h(d),_0)) -> f^#(u(d,h(d),_0),u(d,h(d),_0),u(d,h(d),_0)) [unit] is in U_IR^4. Let p4 = [1, 1]. We unfold the rule of L4 forwards at position p4 with the rule h(d) -> c(b). ==> L5 = f^#(u(d,h(d),_0),k(b),u(d,h(d),_0)) -> f^#(u(d,h(d),_0),u(d,c(b),_0),u(d,h(d),_0)) [unit] is in U_IR^5. Let p5 = [1]. We unfold the rule of L5 forwards at position p5 with the rule u(d,c(_0),_1) -> k(_0). ==> L6 = f^#(u(d,h(d),_0),k(b),u(d,h(d),_0)) -> f^#(u(d,h(d),_0),k(b),u(d,h(d),_0)) [unit] is in U_IR^6. 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 = 23