TSTP Solution File: FLD020-3 by SnakeForV-SAT---1.0
View Problem
- Process Solution
%------------------------------------------------------------------------------
% File : SnakeForV-SAT---1.0
% Problem : FLD020-3 : TPTP v8.1.0. Bugfixed v2.1.0.
% Transfm : none
% Format : tptp:raw
% Command : vampire --input_syntax tptp --proof tptp --output_axiom_names on --mode portfolio --schedule snake_tptp_sat --cores 0 -t %d %s
% Computer : n022.cluster.edu
% Model : x86_64 x86_64
% CPU : Intel(R) Xeon(R) CPU E5-2620 v4 2.10GHz
% Memory : 8042.1875MB
% OS : Linux 3.10.0-693.el7.x86_64
% CPULimit : 300s
% WCLimit : 300s
% DateTime : Wed Aug 31 16:06:40 EDT 2022
% Result : Unsatisfiable 1.38s 0.73s
% Output : Refutation 1.38s
% Verified :
% SZS Type : Refutation
% Derivation depth : 7
% Number of leaves : 6
% Syntax : Number of formulae : 13 ( 6 unt; 0 def)
% Number of atoms : 24 ( 0 equ)
% Maximal formula atoms : 4 ( 1 avg)
% Number of connectives : 24 ( 13 ~; 11 |; 0 &)
% ( 0 <=>; 0 =>; 0 <=; 0 <~>)
% Maximal formula depth : 11 ( 4 avg)
% Maximal term depth : 2 ( 1 avg)
% Number of predicates : 3 ( 2 usr; 1 prp; 0-3 aty)
% Number of functors : 4 ( 4 usr; 3 con; 0-1 aty)
% Number of variables : 15 ( 15 !; 0 ?)
% Comments :
%------------------------------------------------------------------------------
fof(f192,plain,
$false,
inference(subsumption_resolution,[],[f191,f27]) ).
fof(f27,axiom,
defined(a),
file('/export/starexec/sandbox/benchmark/theBenchmark.p',a_is_defined) ).
fof(f191,plain,
~ defined(a),
inference(subsumption_resolution,[],[f190,f30]) ).
fof(f30,axiom,
~ sum(additive_identity,m,additive_identity),
file('/export/starexec/sandbox/benchmark/theBenchmark.p',not_sum_4) ).
fof(f190,plain,
( sum(additive_identity,m,additive_identity)
| ~ defined(a) ),
inference(resolution,[],[f185,f4]) ).
fof(f4,axiom,
! [X0] :
( sum(additive_inverse(X0),X0,additive_identity)
| ~ defined(X0) ),
file('/export/starexec/sandbox/benchmark/theBenchmark.p',existence_of_inverse_addition) ).
fof(f185,plain,
! [X4] :
( ~ sum(additive_inverse(a),a,X4)
| sum(X4,m,additive_identity) ),
inference(subsumption_resolution,[],[f183,f27]) ).
fof(f183,plain,
! [X4] :
( sum(X4,m,additive_identity)
| ~ sum(additive_inverse(a),a,X4)
| ~ defined(a) ),
inference(resolution,[],[f52,f4]) ).
fof(f52,plain,
! [X18,X16,X17] :
( ~ sum(X18,a,X17)
| sum(X16,m,X17)
| ~ sum(X18,a,X16) ),
inference(resolution,[],[f2,f36]) ).
fof(f36,plain,
sum(a,m,a),
inference(resolution,[],[f5,f29]) ).
fof(f29,axiom,
sum(m,a,a),
file('/export/starexec/sandbox/benchmark/theBenchmark.p',sum_3) ).
fof(f5,axiom,
! [X3,X0,X5] :
( ~ sum(X0,X3,X5)
| sum(X3,X0,X5) ),
file('/export/starexec/sandbox/benchmark/theBenchmark.p',commutativity_addition) ).
fof(f2,axiom,
! [X2,X3,X0,X1,X4,X5] :
( ~ sum(X3,X5,X1)
| sum(X4,X5,X2)
| ~ sum(X0,X1,X2)
| ~ sum(X0,X3,X4) ),
file('/export/starexec/sandbox/benchmark/theBenchmark.p',associativity_addition_2) ).
%------------------------------------------------------------------------------
%----ORIGINAL SYSTEM OUTPUT
% 0.11/0.12 % Problem : FLD020-3 : TPTP v8.1.0. Bugfixed v2.1.0.
% 0.11/0.13 % Command : vampire --input_syntax tptp --proof tptp --output_axiom_names on --mode portfolio --schedule snake_tptp_sat --cores 0 -t %d %s
% 0.13/0.34 % Computer : n022.cluster.edu
% 0.13/0.34 % Model : x86_64 x86_64
% 0.13/0.34 % CPU : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz
% 0.13/0.34 % Memory : 8042.1875MB
% 0.13/0.34 % OS : Linux 3.10.0-693.el7.x86_64
% 0.13/0.34 % CPULimit : 300
% 0.13/0.34 % WCLimit : 300
% 0.13/0.34 % DateTime : Mon Aug 29 20:38:41 EDT 2022
% 0.13/0.34 % CPUTime :
% 0.13/0.35 ipcrm: permission denied for id (630620160)
% 0.13/0.35 ipcrm: permission denied for id (630652930)
% 0.13/0.36 ipcrm: permission denied for id (630685699)
% 0.13/0.36 ipcrm: permission denied for id (637763588)
% 0.13/0.36 ipcrm: permission denied for id (630718469)
% 0.13/0.36 ipcrm: permission denied for id (630751238)
% 0.13/0.36 ipcrm: permission denied for id (637796359)
% 0.13/0.36 ipcrm: permission denied for id (636256264)
% 0.13/0.36 ipcrm: permission denied for id (633208841)
% 0.13/0.36 ipcrm: permission denied for id (633241610)
% 0.13/0.36 ipcrm: permission denied for id (636289035)
% 0.13/0.37 ipcrm: permission denied for id (633372686)
% 0.13/0.37 ipcrm: permission denied for id (633405455)
% 0.13/0.37 ipcrm: permission denied for id (633438224)
% 0.13/0.37 ipcrm: permission denied for id (636387345)
% 0.13/0.37 ipcrm: permission denied for id (637894674)
% 0.13/0.37 ipcrm: permission denied for id (633536531)
% 0.13/0.37 ipcrm: permission denied for id (633569300)
% 0.13/0.38 ipcrm: permission denied for id (637960214)
% 0.13/0.38 ipcrm: permission denied for id (631210007)
% 0.13/0.38 ipcrm: permission denied for id (633667608)
% 0.13/0.38 ipcrm: permission denied for id (637992985)
% 0.13/0.38 ipcrm: permission denied for id (631275546)
% 0.13/0.38 ipcrm: permission denied for id (636551195)
% 0.13/0.39 ipcrm: permission denied for id (631341085)
% 0.13/0.39 ipcrm: permission denied for id (633831454)
% 0.13/0.39 ipcrm: permission denied for id (631373855)
% 0.13/0.39 ipcrm: permission denied for id (631472161)
% 0.13/0.39 ipcrm: permission denied for id (638091298)
% 0.13/0.39 ipcrm: permission denied for id (631504931)
% 0.13/0.39 ipcrm: permission denied for id (633929764)
% 0.13/0.39 ipcrm: permission denied for id (631537701)
% 0.13/0.40 ipcrm: permission denied for id (633962534)
% 0.13/0.40 ipcrm: permission denied for id (631570471)
% 0.13/0.40 ipcrm: permission denied for id (633995304)
% 0.13/0.40 ipcrm: permission denied for id (631636009)
% 0.13/0.40 ipcrm: permission denied for id (631668778)
% 0.13/0.40 ipcrm: permission denied for id (634028075)
% 0.13/0.40 ipcrm: permission denied for id (631701548)
% 0.13/0.40 ipcrm: permission denied for id (634060845)
% 0.13/0.41 ipcrm: permission denied for id (631734318)
% 0.13/0.41 ipcrm: permission denied for id (631767087)
% 0.13/0.41 ipcrm: permission denied for id (634093616)
% 0.13/0.41 ipcrm: permission denied for id (631799857)
% 0.13/0.41 ipcrm: permission denied for id (636682290)
% 0.19/0.41 ipcrm: permission denied for id (631832627)
% 0.19/0.41 ipcrm: permission denied for id (634159156)
% 0.19/0.41 ipcrm: permission denied for id (634191925)
% 0.19/0.41 ipcrm: permission denied for id (634224694)
% 0.19/0.42 ipcrm: permission denied for id (634257463)
% 0.19/0.42 ipcrm: permission denied for id (634323000)
% 0.19/0.42 ipcrm: permission denied for id (634355769)
% 0.19/0.42 ipcrm: permission denied for id (631865402)
% 0.19/0.42 ipcrm: permission denied for id (634388539)
% 0.19/0.42 ipcrm: permission denied for id (631898172)
% 0.19/0.42 ipcrm: permission denied for id (634454078)
% 0.19/0.43 ipcrm: permission denied for id (634486847)
% 0.19/0.43 ipcrm: permission denied for id (636747840)
% 0.19/0.43 ipcrm: permission denied for id (634552385)
% 0.19/0.43 ipcrm: permission denied for id (638156866)
% 0.19/0.43 ipcrm: permission denied for id (632029251)
% 0.19/0.43 ipcrm: permission denied for id (634617924)
% 0.19/0.43 ipcrm: permission denied for id (634683462)
% 0.19/0.43 ipcrm: permission denied for id (632094791)
% 0.19/0.44 ipcrm: permission denied for id (636846152)
% 0.19/0.44 ipcrm: permission denied for id (638222409)
% 0.19/0.44 ipcrm: permission denied for id (634781770)
% 0.19/0.44 ipcrm: permission denied for id (638320716)
% 0.19/0.44 ipcrm: permission denied for id (632193101)
% 0.19/0.44 ipcrm: permission denied for id (634880078)
% 0.19/0.45 ipcrm: permission denied for id (638451793)
% 0.19/0.45 ipcrm: permission denied for id (638517331)
% 0.19/0.45 ipcrm: permission denied for id (632291412)
% 0.19/0.45 ipcrm: permission denied for id (637141077)
% 0.19/0.45 ipcrm: permission denied for id (637206614)
% 0.19/0.45 ipcrm: permission denied for id (632324183)
% 0.19/0.45 ipcrm: permission denied for id (638550104)
% 0.19/0.46 ipcrm: permission denied for id (635175001)
% 0.19/0.46 ipcrm: permission denied for id (632356954)
% 0.19/0.46 ipcrm: permission denied for id (635240540)
% 0.19/0.46 ipcrm: permission denied for id (635273309)
% 0.19/0.46 ipcrm: permission denied for id (632520798)
% 0.19/0.46 ipcrm: permission denied for id (638615647)
% 0.19/0.46 ipcrm: permission denied for id (632553568)
% 0.19/0.47 ipcrm: permission denied for id (635338849)
% 0.19/0.47 ipcrm: permission denied for id (637337698)
% 0.19/0.47 ipcrm: permission denied for id (635404387)
% 0.19/0.47 ipcrm: permission denied for id (637370468)
% 0.19/0.47 ipcrm: permission denied for id (635568232)
% 0.19/0.47 ipcrm: permission denied for id (637501545)
% 0.19/0.48 ipcrm: permission denied for id (637534314)
% 0.19/0.48 ipcrm: permission denied for id (635666539)
% 0.19/0.48 ipcrm: permission denied for id (638746732)
% 0.19/0.48 ipcrm: permission denied for id (635732077)
% 0.19/0.48 ipcrm: permission denied for id (635764846)
% 0.19/0.48 ipcrm: permission denied for id (637599855)
% 0.19/0.48 ipcrm: permission denied for id (637632624)
% 0.19/0.48 ipcrm: permission denied for id (635863153)
% 0.19/0.49 ipcrm: permission denied for id (632782962)
% 0.19/0.49 ipcrm: permission denied for id (632815731)
% 0.19/0.49 ipcrm: permission denied for id (632848500)
% 0.19/0.49 ipcrm: permission denied for id (632881269)
% 0.19/0.49 ipcrm: permission denied for id (632914038)
% 0.19/0.49 ipcrm: permission denied for id (632946807)
% 0.19/0.49 ipcrm: permission denied for id (632979576)
% 0.19/0.49 ipcrm: permission denied for id (635895929)
% 0.19/0.50 ipcrm: permission denied for id (635928698)
% 0.19/0.50 ipcrm: permission denied for id (638779515)
% 0.19/0.50 ipcrm: permission denied for id (637698172)
% 0.19/0.50 ipcrm: permission denied for id (633012349)
% 0.19/0.50 ipcrm: permission denied for id (633045118)
% 0.19/0.50 ipcrm: permission denied for id (636092543)
% 0.86/0.63 % (11426)ott+2_1:1_fsr=off:gsp=on:i=50:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/50Mi)
% 1.09/0.63 % (11424)dis+2_1:64_add=large:bce=on:bd=off:i=2:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/2Mi)
% 1.09/0.63 % (11424)Instruction limit reached!
% 1.09/0.63 % (11424)------------------------------
% 1.09/0.63 % (11424)Version: Vampire 4.7 (commit 807e37dd9 on 2022-08-23 09:55:27 +0200)
% 1.09/0.64 % (11440)ott+10_1:1_kws=precedence:tgt=ground:i=482:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/482Mi)
% 1.09/0.64 % (11424)Linked with Z3 4.8.13.0 f03d756e086f81f2596157241e0decfb1c982299 z3-4.8.4-5390-gf03d756e0
% 1.09/0.64 % (11424)Termination reason: Unknown
% 1.09/0.64 % (11424)Termination phase: Blocked clause elimination
% 1.09/0.64
% 1.09/0.64 % (11424)Memory used [KB]: 895
% 1.09/0.64 % (11424)Time elapsed: 0.003 s
% 1.09/0.64 % (11424)Instructions burned: 3 (million)
% 1.09/0.64 % (11424)------------------------------
% 1.09/0.64 % (11424)------------------------------
% 1.09/0.64 % (11442)ins+10_1:1_awrs=decay:awrsf=30:bsr=unit_only:foolp=on:igrr=8/457:igs=10:igwr=on:nwc=1.5:sp=weighted_frequency:to=lpo:uhcvi=on:i=68:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/68Mi)
% 1.09/0.65 % (11434)ott+10_1:1_tgt=ground:i=100:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/100Mi)
% 1.09/0.65 % (11425)ott-1_1:6_av=off:cond=on:fsr=off:nwc=3.0:i=51:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/51Mi)
% 1.09/0.66 % (11418)ott+4_1:1_av=off:bd=off:nwc=5.0:s2a=on:s2at=2.0:slsq=on:slsqc=2:slsql=off:slsqr=1,2:sp=frequency:i=37:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/37Mi)
% 1.09/0.66 % (11416)fmb+10_1:1_bce=on:fmbsr=1.5:nm=4:skr=on:i=191324:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/191324Mi)
% 1.38/0.66 % (11427)ott+10_1:32_bd=off:fsr=off:newcnf=on:tgt=full:i=100:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/100Mi)
% 1.38/0.67 % (11430)ins+10_1:1_awrs=decay:awrsf=30:bsr=unit_only:foolp=on:igrr=8/457:igs=10:igwr=on:nwc=1.5:sp=weighted_frequency:to=lpo:uhcvi=on:i=68:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/68Mi)
% 1.38/0.68 % (11422)fmb+10_1:1_fmbsr=2.0:nm=4:skr=on:i=51:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/51Mi)
% 1.38/0.68 % (11429)ott+10_1:5_bd=off:tgt=full:i=99:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/99Mi)
% 1.38/0.68 % (11423)dis+10_1:1_fsd=on:sp=occurrence:i=7:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/7Mi)
% 1.38/0.68 % (11428)ott+10_1:28_bd=off:bs=on:tgt=ground:i=101:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/101Mi)
% 1.38/0.68 TRYING [1]
% 1.38/0.68 TRYING [2]
% 1.38/0.68 TRYING [3]
% 1.38/0.68 % (11419)ott+10_1:32_bd=off:fsr=off:newcnf=on:tgt=full:i=51:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/51Mi)
% 1.38/0.68 % (11439)ott+11_1:1_drc=off:nwc=5.0:slsq=on:slsqc=1:spb=goal_then_units:to=lpo:i=467:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/467Mi)
% 1.38/0.68 % (11417)ott+10_1:32_abs=on:br=off:urr=ec_only:i=50:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/50Mi)
% 1.38/0.68 % (11417)Refutation not found, incomplete strategy% (11417)------------------------------
% 1.38/0.68 % (11417)Version: Vampire 4.7 (commit 807e37dd9 on 2022-08-23 09:55:27 +0200)
% 1.38/0.68 % (11417)Linked with Z3 4.8.13.0 f03d756e086f81f2596157241e0decfb1c982299 z3-4.8.4-5390-gf03d756e0
% 1.38/0.68 % (11417)Termination reason: Refutation not found, incomplete strategy
% 1.38/0.68
% 1.38/0.68 % (11417)Memory used [KB]: 5373
% 1.38/0.68 % (11417)Time elapsed: 0.133 s
% 1.38/0.68 % (11417)Instructions burned: 1 (million)
% 1.38/0.68 % (11417)------------------------------
% 1.38/0.68 % (11417)------------------------------
% 1.38/0.69 % (11421)dis+34_1:32_abs=on:add=off:bsr=on:gsp=on:sp=weighted_frequency:i=48:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/48Mi)
% 1.38/0.69 % (11441)ott+10_1:5_bd=off:tgt=full:i=500:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/500Mi)
% 1.38/0.69 % (11431)ott+11_2:3_av=off:fde=unused:nwc=5.0:tgt=ground:i=75:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/75Mi)
% 1.38/0.69 % (11420)ott+33_1:4_s2a=on:tgt=ground:i=51:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/51Mi)
% 1.38/0.69 % (11438)dis+21_1:1_av=off:er=filter:slsq=on:slsqc=0:slsqr=1,1:sp=frequency:to=lpo:i=498:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/498Mi)
% 1.38/0.69 % (11433)fmb+10_1:1_bce=on:i=59:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/59Mi)
% 1.38/0.69 % (11432)dis+34_1:32_abs=on:add=off:bsr=on:gsp=on:sp=weighted_frequency:i=99:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/99Mi)
% 1.38/0.69 TRYING [1]
% 1.38/0.69 TRYING [2]
% 1.38/0.69 % (11443)ott+11_2:3_av=off:fde=unused:nwc=5.0:tgt=ground:i=177:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/177Mi)
% 1.38/0.70 TRYING [3]
% 1.38/0.70 % (11444)ott+33_1:4_s2a=on:tgt=ground:i=439:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/439Mi)
% 1.38/0.70 TRYING [1]
% 1.38/0.70 % (11437)ott+3_1:1_gsp=on:lcm=predicate:i=138:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/138Mi)
% 1.38/0.70 TRYING [2]
% 1.38/0.70 TRYING [3]
% 1.38/0.70 % (11435)ott+4_1:1_av=off:bd=off:nwc=5.0:rp=on:s2a=on:s2at=2.0:slsq=on:slsqc=2:slsql=off:slsqr=1,2:sp=frequency:i=100:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/100Mi)
% 1.38/0.70 % (11436)ott+10_1:8_bsd=on:fsd=on:lcm=predicate:nwc=5.0:s2a=on:s2at=1.5:spb=goal_then_units:i=176:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/176Mi)
% 1.38/0.70 % (11423)Instruction limit reached!
% 1.38/0.70 % (11423)------------------------------
% 1.38/0.70 % (11423)Version: Vampire 4.7 (commit 807e37dd9 on 2022-08-23 09:55:27 +0200)
% 1.38/0.70 % (11423)Linked with Z3 4.8.13.0 f03d756e086f81f2596157241e0decfb1c982299 z3-4.8.4-5390-gf03d756e0
% 1.38/0.70 % (11423)Termination reason: Unknown
% 1.38/0.70 % (11423)Termination phase: Saturation
% 1.38/0.70
% 1.38/0.70 % (11423)Memory used [KB]: 5500
% 1.38/0.70 % (11423)Time elapsed: 0.129 s
% 1.38/0.70 % (11423)Instructions burned: 7 (million)
% 1.38/0.70 % (11423)------------------------------
% 1.38/0.70 % (11423)------------------------------
% 1.38/0.70 % (11436)First to succeed.
% 1.38/0.71 TRYING [4]
% 1.38/0.71 % (11418)Instruction limit reached!
% 1.38/0.71 % (11418)------------------------------
% 1.38/0.71 % (11418)Version: Vampire 4.7 (commit 807e37dd9 on 2022-08-23 09:55:27 +0200)
% 1.38/0.71 % (11418)Linked with Z3 4.8.13.0 f03d756e086f81f2596157241e0decfb1c982299 z3-4.8.4-5390-gf03d756e0
% 1.38/0.71 % (11418)Termination reason: Unknown
% 1.38/0.71 % (11418)Termination phase: Saturation
% 1.38/0.71
% 1.38/0.71 % (11418)Memory used [KB]: 1279
% 1.38/0.71 % (11418)Time elapsed: 0.172 s
% 1.38/0.71 % (11418)Instructions burned: 37 (million)
% 1.38/0.71 % (11418)------------------------------
% 1.38/0.71 % (11418)------------------------------
% 1.38/0.72 % (11445)ott+10_7:2_awrs=decay:awrsf=8:bd=preordered:drc=off:fd=preordered:fde=unused:fsr=off:slsq=on:slsqc=2:slsqr=5,8:sp=const_min:spb=units:to=lpo:i=355:si=on:rawr=on:rtra=on_0 on theBenchmark for (2998ds/355Mi)
% 1.38/0.72 TRYING [4]
% 1.38/0.73 % (11436)Refutation found. Thanks to Tanya!
% 1.38/0.73 % SZS status Unsatisfiable for theBenchmark
% 1.38/0.73 % SZS output start Proof for theBenchmark
% See solution above
% 1.38/0.73 % (11436)------------------------------
% 1.38/0.73 % (11436)Version: Vampire 4.7 (commit 807e37dd9 on 2022-08-23 09:55:27 +0200)
% 1.38/0.73 % (11436)Linked with Z3 4.8.13.0 f03d756e086f81f2596157241e0decfb1c982299 z3-4.8.4-5390-gf03d756e0
% 1.38/0.73 % (11436)Termination reason: Refutation
% 1.38/0.73
% 1.38/0.73 % (11436)Memory used [KB]: 5500
% 1.38/0.73 % (11436)Time elapsed: 0.149 s
% 1.38/0.73 % (11436)Instructions burned: 8 (million)
% 1.38/0.73 % (11436)------------------------------
% 1.38/0.73 % (11436)------------------------------
% 1.38/0.73 % (11282)Success in time 0.373 s
%------------------------------------------------------------------------------