%------------------------------------------------------------------------------
% File : Leo-III---1.8.0
% Problem : PUZ081^3 : TPTP v9.3.1. Released v3.6.0.
% Transfm : none
% Format : tptp:raw
% Command : java -Xss128m -Xmx2g -Xms1g -jar /export/starexec/sandbox2/solver/bin/leo3.jar /export/starexec/sandbox2/benchmark/theBenchmark.p -t 300 -p --atp eprover=/export/starexec/sandbox2/solver/bin/externals/eprover --instantiate 39
% Computer : n017.cluster.edu
% Model : x86_64 x86_64
% CPU : Intel(R) Xeon(R) CPU E5-2620 v4 2.10GHz
% Memory : 8046.5625MB
% OS : Linux 6.8.0-71-generic
% CPULimit : 300s
% WCLimit : 300s
% DateTime : Wed Sep 30 08:20:45 AM UTC 2026
% Result : Theorem 4.38s 2.58s
% Output : Refutation 4.73s
% Verified :
% SZS Type : Refutation
% Derivation depth : 3
% Number of leaves : 6
% Syntax : Number of formulae : 14 ( 3 unt; 0 typ; 0 def)
% Number of atoms : 31 ( 2 equ; 0 cnn)
% Maximal formula atoms : 3 ( 2 avg)
% Number of connectives : 59 ( 10 ~; 0 |; 9 &; 36 @)
% ( 0 <=>; 4 =>; 0 <=; 0 <~>)
% Maximal formula depth : 7 ( 5 avg)
% Number of types : 2 ( 0 usr)
% Number of type conns : 0 ( 0 >; 0 *; 0 +; 0 <<)
% Number of symbols : 7 ( 5 usr; 3 con; 0-2 aty)
% Number of variables : 16 ( 0 ^; 10 !; 6 ?; 16 :)
% Comments :
%------------------------------------------------------------------------------
thf(mel_decl,type,
mel: $i ).
thf(zoey_decl,type,
zoey: $i ).
thf(knight_decl,type,
knight: $i > $o ).
thf(knave_decl,type,
knave: $i > $o ).
thf(says_decl,type,
says: $i > $o > $o ).
thf(7,axiom,
( says @ mel
@ ( ~ ( knave @ zoey )
& ~ ( knave @ mel ) ) ),
file('/export/starexec/sandbox2/benchmark/theBenchmark.p',mel_speaks) ).
thf(20,plain,
( says @ mel
@ ( ~ ( knave @ zoey )
& ~ ( knave @ mel ) ) ),
inference(defexp_and_simp_and_etaexpand,[status(thm)],[7]) ).
thf(5,axiom,
! [A: $i,B: $o] :
( ( ( knave @ A )
& ( says @ A @ B ) )
=> ~ B ),
file('/export/starexec/sandbox2/benchmark/theBenchmark.p',knaves_lie) ).
thf(17,plain,
! [A: $i,B: $o] :
( ( ( knave @ A )
& ( says @ A @ B ) )
=> ~ B ),
inference(defexp_and_simp_and_etaexpand,[status(thm)],[5]) ).
thf(3,axiom,
! [A: $i] :
( ( knight @ A )
!= ( knave @ A ) ),
file('/export/starexec/sandbox2/benchmark/theBenchmark.p',knights_xor_knaves) ).
thf(11,plain,
! [A: $i] :
( ( knight @ A )
!= ( knave @ A ) ),
inference(defexp_and_simp_and_etaexpand,[status(thm)],[3]) ).
thf(1,conjecture,
? [A: $i,B: $i] :
( ( knight @ A )
& ( knave @ B ) ),
file('/export/starexec/sandbox2/benchmark/theBenchmark.p',who_is_knight_and_knave) ).
thf(2,negated_conjecture,
~ ? [A: $i,B: $i] :
( ( knight @ A )
& ( knave @ B ) ),
inference(neg_conjecture,[status(cth)],[1]) ).
thf(8,plain,
~ ? [A: $i,B: $i] :
( ( knight @ A )
& ( knave @ B ) ),
inference(defexp_and_simp_and_etaexpand,[status(thm)],[2]) ).
thf(6,axiom,
says @ zoey @ ( knave @ mel ),
file('/export/starexec/sandbox2/benchmark/theBenchmark.p',zoey_speaks) ).
thf(19,plain,
says @ zoey @ ( knave @ mel ),
inference(defexp_and_simp_and_etaexpand,[status(thm)],[6]) ).
thf(4,axiom,
! [A: $i,B: $o] :
( ( ( knight @ A )
& ( says @ A @ B ) )
=> B ),
file('/export/starexec/sandbox2/benchmark/theBenchmark.p',knights_tell_truth) ).
thf(15,plain,
! [A: $i,B: $o] :
( ( ( knight @ A )
& ( says @ A @ B ) )
=> B ),
inference(defexp_and_simp_and_etaexpand,[status(thm)],[4]) ).
thf(21,plain,
$false,
inference(e,[status(thm)],[20,17,11,8,19,15]) ).
%------------------------------------------------------------------------------
%----ORIGINAL SYSTEM OUTPUT
% 0.00/0.04 % Problem : PUZ081^3 : TPTP v9.3.1. Released v3.6.0.
% 0.00/0.10 % Command : java -Xss128m -Xmx2g -Xms1g -jar /export/starexec/sandbox2/solver/bin/leo3.jar /export/starexec/sandbox2/benchmark/theBenchmark.p -t 300 -p --atp eprover=/export/starexec/sandbox2/solver/bin/externals/eprover --instantiate 39
% 0.24/0.30 % Computer : n017.cluster.edu
% 0.24/0.30 % Model : x86_64 x86_64
% 0.24/0.30 % CPU : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz
% 0.24/0.30 % Memory : 8046.5625MB
% 0.24/0.30 % OS : Linux 6.8.0-71-generic
% 0.24/0.30 % CPULimit : 300
% 0.24/0.30 % WCLimit : 300
% 0.24/0.30 % DateTime : Tue Sep 29 13:17:07 UTC 2026
% 0.24/0.30 % CPUTime :
% 0.24/0.30 Running java -Xss128m -Xmx2g -Xms1g -jar /export/starexec/sandbox2/solver/bin/leo3.jar /export/starexec/sandbox2/benchmark/theBenchmark.p -t 300 -p --atp eprover=/export/starexec/sandbox2/solver/bin/externals/eprover --instantiate 39
% 1.18/1.02 % [INFO] Parsing problem /export/starexec/sandbox2/benchmark/theBenchmark.p ...
% 1.74/1.25 % [INFO] Parsing done (222ms).
% 1.74/1.27 % [INFO] Running in sequential loop mode.
% 2.58/1.79 % [INFO] eprover registered as external prover.
% 2.58/1.80 % [INFO] Scanning for conjecture ...
% 2.78/1.89 % [INFO] Found a conjecture (or negated_conjecture) and 5 axioms. Running axiom selection ...
% 2.98/1.93 % [INFO] Axiom selection finished. Selected 5 axioms (removed 0 axioms).
% 2.98/1.94 % [INFO] Problem is higher-order (TPTP THF).
% 2.98/1.95 % [INFO] Type checking passed.
% 2.98/1.95 % [CONFIG] Using configuration: timeout(300) with strategy<name(default),share(1.0),primSubst(3),sos(false),unifierCount(4),uniDepth(8),boolExt(true),choice(true),renaming(true),funcspec(false), domConstr(0),specialInstances(39),restrictUniAttempts(true),termOrdering(CPO)>. Searching for refutation ...
% 4.38/2.58 % External prover 'e' found a proof!
% 4.38/2.58 % [INFO] Killing All external provers ...
% 4.38/2.58 % Time passed: 2066ms (effective reasoning time: 1297ms)
% 4.38/2.58 % Solved by strategy<name(default),share(1.0),primSubst(3),sos(false),unifierCount(4),uniDepth(8),boolExt(true),choice(true),renaming(true),funcspec(false), domConstr(0),specialInstances(39),restrictUniAttempts(true),termOrdering(CPO)>
% 4.38/2.58 % Axioms used in derivation (5): zoey_speaks, mel_speaks, knights_xor_knaves, knights_tell_truth, knaves_lie
% 4.38/2.58 % No. of inferences in proof: 14
% 4.38/2.58 % SZS status Theorem for /export/starexec/sandbox2/benchmark/theBenchmark.p : 2066 ms resp. 1297 ms w/o parsing
% 4.73/2.64 % SZS output start Refutation for /export/starexec/sandbox2/benchmark/theBenchmark.p
% See solution above
% 4.73/2.64 % [INFO] Killing All external provers ...
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