/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 = 3] a__length(cons(_0,zeros)) -> a__length(cons(0,zeros)) Let l be the left-hand side and r be the right-hand side of this rule. Let p = epsilon, theta1 = {} and theta2 = {_0->0}. We have r|p = a__length(cons(0,zeros)) and theta2(theta1(l)) = theta1(r|p). Hence, the term theta1(l) = a__length(cons(_0,zeros)) 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 = [a__and^#(tt,_0) -> mark^#(_0), mark^#(and(_0,_1)) -> a__and^#(mark(_0),_1), a__length^#(cons(_0,_1)) -> mark^#(_1), a__length^#(cons(_0,_1)) -> a__length^#(mark(_1)), mark^#(length(_0)) -> a__length^#(mark(_0)), mark^#(and(_0,_1)) -> mark^#(_0), mark^#(length(_0)) -> mark^#(_0), mark^#(cons(_0,_1)) -> mark^#(_0), mark^#(s(_0)) -> mark^#(_0)] TRS = {a__zeros -> cons(0,zeros), a__and(tt,_0) -> mark(_0), a__length(nil) -> 0, a__length(cons(_0,_1)) -> s(a__length(mark(_1))), mark(zeros) -> a__zeros, mark(and(_0,_1)) -> a__and(mark(_0),_1), mark(length(_0)) -> a__length(mark(_0)), mark(cons(_0,_1)) -> cons(mark(_0),_1), mark(0) -> 0, mark(tt) -> tt, mark(nil) -> nil, mark(s(_0)) -> s(mark(_0)), a__zeros -> zeros, a__and(_0,_1) -> and(_0,_1), a__length(_0) -> length(_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=false, max=-1) # max_depth=3, unfold_variables=false: # Iteration 0: no loop found, 9 unfolded rules generated. # Iteration 1: no loop found, 69 unfolded rules generated. # Iteration 2: no loop found, 154 unfolded rules generated. # Iteration 3: success, found a loop, 96 unfolded rules generated. Here is the successful unfolding. Let IR be the TRS under analysis. L0 = a__length^#(cons(_0,_1)) -> a__length^#(mark(_1)) [trans] is in U_IR^0. D = a__length^#(cons(_0,_1)) -> mark^#(_1) is a dependency pair of IR. We build a composed triple from L0 and D. ==> L1 = [a__length^#(cons(_0,_1)) -> a__length^#(mark(_1)), a__length^#(cons(_2,_3)) -> mark^#(_3)] [comp] is in U_IR^1. Let p1 = [0]. We unfold the first rule of L1 forwards at position p1 with the rule mark(zeros) -> a__zeros. ==> L2 = [a__length^#(cons(_0,zeros)) -> a__length^#(a__zeros), a__length^#(cons(_1,_2)) -> mark^#(_2)] [comp] is in U_IR^2. Let p2 = [0]. We unfold the first rule of L2 forwards at position p2 with the rule a__zeros -> cons(0,zeros). ==> L3 = [a__length^#(cons(_0,zeros)) -> a__length^#(cons(0,zeros)), a__length^#(cons(_1,_2)) -> mark^#(_2)] [comp] 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 = 1116