TSTP Solution File: SWC071+1 by SRASS---0.1
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- Process Solution
%------------------------------------------------------------------------------
% File : SRASS---0.1
% Problem : SWC071+1 : TPTP v5.0.0. Released v2.4.0.
% Transfm : none
% Format : tptp
% Command : SRASS -q2 -a 0 10 10 10 -i3 -n60 %s
% Computer : art03.cs.miami.edu
% Model : i686 i686
% CPU : Intel(R) Pentium(R) 4 CPU 2.80GHz @ 2793MHz
% Memory : 2018MB
% OS : Linux 2.6.26.8-57.fc8
% CPULimit : 300s
% DateTime : Thu Dec 30 06:58:40 EST 2010
% Result : Theorem 1.32s
% Output : Solution 1.32s
% Verified :
% SZS Type : None (Parsing solution fails)
% Syntax : Number of formulae : 0
% Comments :
%------------------------------------------------------------------------------
%----ERROR: Could not form TPTP format derivation
%------------------------------------------------------------------------------
%----ORIGINAL SYSTEM OUTPUT
% Reading problem from /tmp/SystemOnTPTP17253/SWC071+1.tptp
% Adding relevance values
% Extracting the conjecture
% Sorting axioms by relevance
% Looking for THM ...
% found
% SZS status THM for /tmp/SystemOnTPTP17253/SWC071+1.tptp
% SZS output start Solution for /tmp/SystemOnTPTP17253/SWC071+1.tptp
% TreeLimitedRun: ----------------------------------------------------------
% TreeLimitedRun: /home/graph/tptp/Systems/EP---1.2/eproof --print-statistics -xAuto -tAuto --cpu-limit=60 --proof-time-unlimited --memory-limit=Auto --tstp-in --tstp-out /tmp/SRASS.s.p
% TreeLimitedRun: CPU time limit is 60s
% TreeLimitedRun: WC time limit is 120s
% TreeLimitedRun: PID is 17349
% TreeLimitedRun: ----------------------------------------------------------
% PrfWatch: 0.00 CPU 0.00 WC
% # Preprocessing time : 0.031 s
% # Problem is unsatisfiable (or provable), constructing proof object
% # SZS status Theorem
% # SZS output start CNFRefutation.
% fof(4, axiom,![X1]:(ssList(X1)=>![X2]:(ssList(X2)=>(segmentP(X1,X2)<=>?[X3]:(ssList(X3)&?[X4]:(ssList(X4)&app(app(X3,X2),X4)=X1))))),file('/tmp/SRASS.s.p', ax7)).
% fof(5, axiom,![X1]:(ssList(X1)=>![X2]:(ssList(X2)=>(neq(X1,X2)<=>~(X1=X2)))),file('/tmp/SRASS.s.p', ax15)).
% fof(7, axiom,ssList(nil),file('/tmp/SRASS.s.p', ax17)).
% fof(11, axiom,![X1]:(ssList(X1)=>![X2]:(ssItem(X2)=>~(nil=cons(X2,X1)))),file('/tmp/SRASS.s.p', ax21)).
% fof(22, axiom,![X1]:(ssList(X1)=>segmentP(X1,X1)),file('/tmp/SRASS.s.p', ax55)).
% fof(96, conjecture,![X1]:(ssList(X1)=>![X2]:(ssList(X2)=>![X3]:(ssList(X3)=>![X4]:(ssList(X4)=>((((~(X2=X4)|~(X1=X3))|?[X5]:(((ssList(X5)&neq(X5,nil))&segmentP(X2,X5))&segmentP(X1,X5)))|(nil=X2&nil=X1))|(![X6]:(ssItem(X6)=>![X7]:(ssList(X7)=>![X8]:(ssList(X8)=>(((~(cons(X6,nil)=X3)|~(app(app(X7,X3),X8)=X4))|?[X9]:((ssItem(X9)&memberP(X7,X9))<(X6,X9)))|?[X10]:((ssItem(X10)&memberP(X8,X10))<(X10,X6))))))&(~(nil=X4)|~(nil=X3)))))))),file('/tmp/SRASS.s.p', co1)).
% fof(97, negated_conjecture,~(![X1]:(ssList(X1)=>![X2]:(ssList(X2)=>![X3]:(ssList(X3)=>![X4]:(ssList(X4)=>((((~(X2=X4)|~(X1=X3))|?[X5]:(((ssList(X5)&neq(X5,nil))&segmentP(X2,X5))&segmentP(X1,X5)))|(nil=X2&nil=X1))|(![X6]:(ssItem(X6)=>![X7]:(ssList(X7)=>![X8]:(ssList(X8)=>(((~(cons(X6,nil)=X3)|~(app(app(X7,X3),X8)=X4))|?[X9]:((ssItem(X9)&memberP(X7,X9))<(X6,X9)))|?[X10]:((ssItem(X10)&memberP(X8,X10))<(X10,X6))))))&(~(nil=X4)|~(nil=X3))))))))),inference(assume_negation,[status(cth)],[96])).
% fof(123, plain,![X1]:(~(ssList(X1))|![X2]:(~(ssList(X2))|((~(segmentP(X1,X2))|?[X3]:(ssList(X3)&?[X4]:(ssList(X4)&app(app(X3,X2),X4)=X1)))&(![X3]:(~(ssList(X3))|![X4]:(~(ssList(X4))|~(app(app(X3,X2),X4)=X1)))|segmentP(X1,X2))))),inference(fof_nnf,[status(thm)],[4])).
% fof(124, plain,![X5]:(~(ssList(X5))|![X6]:(~(ssList(X6))|((~(segmentP(X5,X6))|?[X7]:(ssList(X7)&?[X8]:(ssList(X8)&app(app(X7,X6),X8)=X5)))&(![X9]:(~(ssList(X9))|![X10]:(~(ssList(X10))|~(app(app(X9,X6),X10)=X5)))|segmentP(X5,X6))))),inference(variable_rename,[status(thm)],[123])).
% fof(125, plain,![X5]:(~(ssList(X5))|![X6]:(~(ssList(X6))|((~(segmentP(X5,X6))|(ssList(esk5_2(X5,X6))&(ssList(esk6_2(X5,X6))&app(app(esk5_2(X5,X6),X6),esk6_2(X5,X6))=X5)))&(![X9]:(~(ssList(X9))|![X10]:(~(ssList(X10))|~(app(app(X9,X6),X10)=X5)))|segmentP(X5,X6))))),inference(skolemize,[status(esa)],[124])).
% fof(126, plain,![X5]:![X6]:![X9]:![X10]:((((((~(ssList(X10))|~(app(app(X9,X6),X10)=X5))|~(ssList(X9)))|segmentP(X5,X6))&(~(segmentP(X5,X6))|(ssList(esk5_2(X5,X6))&(ssList(esk6_2(X5,X6))&app(app(esk5_2(X5,X6),X6),esk6_2(X5,X6))=X5))))|~(ssList(X6)))|~(ssList(X5))),inference(shift_quantors,[status(thm)],[125])).
% fof(127, plain,![X5]:![X6]:![X9]:![X10]:((((((~(ssList(X10))|~(app(app(X9,X6),X10)=X5))|~(ssList(X9)))|segmentP(X5,X6))|~(ssList(X6)))|~(ssList(X5)))&((((ssList(esk5_2(X5,X6))|~(segmentP(X5,X6)))|~(ssList(X6)))|~(ssList(X5)))&((((ssList(esk6_2(X5,X6))|~(segmentP(X5,X6)))|~(ssList(X6)))|~(ssList(X5)))&(((app(app(esk5_2(X5,X6),X6),esk6_2(X5,X6))=X5|~(segmentP(X5,X6)))|~(ssList(X6)))|~(ssList(X5)))))),inference(distribute,[status(thm)],[126])).
% cnf(131,plain,(segmentP(X1,X2)|~ssList(X1)|~ssList(X2)|~ssList(X3)|app(app(X3,X2),X4)!=X1|~ssList(X4)),inference(split_conjunct,[status(thm)],[127])).
% fof(132, plain,![X1]:(~(ssList(X1))|![X2]:(~(ssList(X2))|((~(neq(X1,X2))|~(X1=X2))&(X1=X2|neq(X1,X2))))),inference(fof_nnf,[status(thm)],[5])).
% fof(133, plain,![X3]:(~(ssList(X3))|![X4]:(~(ssList(X4))|((~(neq(X3,X4))|~(X3=X4))&(X3=X4|neq(X3,X4))))),inference(variable_rename,[status(thm)],[132])).
% fof(134, plain,![X3]:![X4]:((~(ssList(X4))|((~(neq(X3,X4))|~(X3=X4))&(X3=X4|neq(X3,X4))))|~(ssList(X3))),inference(shift_quantors,[status(thm)],[133])).
% fof(135, plain,![X3]:![X4]:((((~(neq(X3,X4))|~(X3=X4))|~(ssList(X4)))|~(ssList(X3)))&(((X3=X4|neq(X3,X4))|~(ssList(X4)))|~(ssList(X3)))),inference(distribute,[status(thm)],[134])).
% cnf(136,plain,(neq(X1,X2)|X1=X2|~ssList(X1)|~ssList(X2)),inference(split_conjunct,[status(thm)],[135])).
% cnf(142,plain,(ssList(nil)),inference(split_conjunct,[status(thm)],[7])).
% fof(160, plain,![X1]:(~(ssList(X1))|![X2]:(~(ssItem(X2))|~(nil=cons(X2,X1)))),inference(fof_nnf,[status(thm)],[11])).
% fof(161, plain,![X3]:(~(ssList(X3))|![X4]:(~(ssItem(X4))|~(nil=cons(X4,X3)))),inference(variable_rename,[status(thm)],[160])).
% fof(162, plain,![X3]:![X4]:((~(ssItem(X4))|~(nil=cons(X4,X3)))|~(ssList(X3))),inference(shift_quantors,[status(thm)],[161])).
% cnf(163,plain,(~ssList(X1)|nil!=cons(X2,X1)|~ssItem(X2)),inference(split_conjunct,[status(thm)],[162])).
% fof(208, plain,![X1]:(~(ssList(X1))|segmentP(X1,X1)),inference(fof_nnf,[status(thm)],[22])).
% fof(209, plain,![X2]:(~(ssList(X2))|segmentP(X2,X2)),inference(variable_rename,[status(thm)],[208])).
% cnf(210,plain,(segmentP(X1,X1)|~ssList(X1)),inference(split_conjunct,[status(thm)],[209])).
% fof(567, negated_conjecture,?[X1]:(ssList(X1)&?[X2]:(ssList(X2)&?[X3]:(ssList(X3)&?[X4]:(ssList(X4)&((((X2=X4&X1=X3)&![X5]:(((~(ssList(X5))|~(neq(X5,nil)))|~(segmentP(X2,X5)))|~(segmentP(X1,X5))))&(~(nil=X2)|~(nil=X1)))&(?[X6]:(ssItem(X6)&?[X7]:(ssList(X7)&?[X8]:(ssList(X8)&(((cons(X6,nil)=X3&app(app(X7,X3),X8)=X4)&![X9]:((~(ssItem(X9))|~(memberP(X7,X9)))|~(lt(X6,X9))))&![X10]:((~(ssItem(X10))|~(memberP(X8,X10)))|~(lt(X10,X6)))))))|(nil=X4&nil=X3))))))),inference(fof_nnf,[status(thm)],[97])).
% fof(568, negated_conjecture,?[X11]:(ssList(X11)&?[X12]:(ssList(X12)&?[X13]:(ssList(X13)&?[X14]:(ssList(X14)&((((X12=X14&X11=X13)&![X15]:(((~(ssList(X15))|~(neq(X15,nil)))|~(segmentP(X12,X15)))|~(segmentP(X11,X15))))&(~(nil=X12)|~(nil=X11)))&(?[X16]:(ssItem(X16)&?[X17]:(ssList(X17)&?[X18]:(ssList(X18)&(((cons(X16,nil)=X13&app(app(X17,X13),X18)=X14)&![X19]:((~(ssItem(X19))|~(memberP(X17,X19)))|~(lt(X16,X19))))&![X20]:((~(ssItem(X20))|~(memberP(X18,X20)))|~(lt(X20,X16)))))))|(nil=X14&nil=X13))))))),inference(variable_rename,[status(thm)],[567])).
% fof(569, negated_conjecture,(ssList(esk48_0)&(ssList(esk49_0)&(ssList(esk50_0)&(ssList(esk51_0)&((((esk49_0=esk51_0&esk48_0=esk50_0)&![X15]:(((~(ssList(X15))|~(neq(X15,nil)))|~(segmentP(esk49_0,X15)))|~(segmentP(esk48_0,X15))))&(~(nil=esk49_0)|~(nil=esk48_0)))&((ssItem(esk52_0)&(ssList(esk53_0)&(ssList(esk54_0)&(((cons(esk52_0,nil)=esk50_0&app(app(esk53_0,esk50_0),esk54_0)=esk51_0)&![X19]:((~(ssItem(X19))|~(memberP(esk53_0,X19)))|~(lt(esk52_0,X19))))&![X20]:((~(ssItem(X20))|~(memberP(esk54_0,X20)))|~(lt(X20,esk52_0)))))))|(nil=esk51_0&nil=esk50_0))))))),inference(skolemize,[status(esa)],[568])).
% fof(570, negated_conjecture,![X15]:![X19]:![X20]:((((((((((((~(ssItem(X20))|~(memberP(esk54_0,X20)))|~(lt(X20,esk52_0)))&(((~(ssItem(X19))|~(memberP(esk53_0,X19)))|~(lt(esk52_0,X19)))&(cons(esk52_0,nil)=esk50_0&app(app(esk53_0,esk50_0),esk54_0)=esk51_0)))&ssList(esk54_0))&ssList(esk53_0))&ssItem(esk52_0))|(nil=esk51_0&nil=esk50_0))&(((((~(ssList(X15))|~(neq(X15,nil)))|~(segmentP(esk49_0,X15)))|~(segmentP(esk48_0,X15)))&(esk49_0=esk51_0&esk48_0=esk50_0))&(~(nil=esk49_0)|~(nil=esk48_0))))&ssList(esk51_0))&ssList(esk50_0))&ssList(esk49_0))&ssList(esk48_0)),inference(shift_quantors,[status(thm)],[569])).
% fof(571, negated_conjecture,![X15]:![X19]:![X20]:(((((((((((nil=esk51_0|((~(ssItem(X20))|~(memberP(esk54_0,X20)))|~(lt(X20,esk52_0))))&(nil=esk50_0|((~(ssItem(X20))|~(memberP(esk54_0,X20)))|~(lt(X20,esk52_0)))))&(((nil=esk51_0|((~(ssItem(X19))|~(memberP(esk53_0,X19)))|~(lt(esk52_0,X19))))&(nil=esk50_0|((~(ssItem(X19))|~(memberP(esk53_0,X19)))|~(lt(esk52_0,X19)))))&(((nil=esk51_0|cons(esk52_0,nil)=esk50_0)&(nil=esk50_0|cons(esk52_0,nil)=esk50_0))&((nil=esk51_0|app(app(esk53_0,esk50_0),esk54_0)=esk51_0)&(nil=esk50_0|app(app(esk53_0,esk50_0),esk54_0)=esk51_0)))))&((nil=esk51_0|ssList(esk54_0))&(nil=esk50_0|ssList(esk54_0))))&((nil=esk51_0|ssList(esk53_0))&(nil=esk50_0|ssList(esk53_0))))&((nil=esk51_0|ssItem(esk52_0))&(nil=esk50_0|ssItem(esk52_0))))&(((((~(ssList(X15))|~(neq(X15,nil)))|~(segmentP(esk49_0,X15)))|~(segmentP(esk48_0,X15)))&(esk49_0=esk51_0&esk48_0=esk50_0))&(~(nil=esk49_0)|~(nil=esk48_0))))&ssList(esk51_0))&ssList(esk50_0))&ssList(esk49_0))&ssList(esk48_0)),inference(distribute,[status(thm)],[570])).
% cnf(572,negated_conjecture,(ssList(esk48_0)),inference(split_conjunct,[status(thm)],[571])).
% cnf(573,negated_conjecture,(ssList(esk49_0)),inference(split_conjunct,[status(thm)],[571])).
% cnf(576,negated_conjecture,(nil!=esk48_0|nil!=esk49_0),inference(split_conjunct,[status(thm)],[571])).
% cnf(577,negated_conjecture,(esk48_0=esk50_0),inference(split_conjunct,[status(thm)],[571])).
% cnf(578,negated_conjecture,(esk49_0=esk51_0),inference(split_conjunct,[status(thm)],[571])).
% cnf(579,negated_conjecture,(~segmentP(esk48_0,X1)|~segmentP(esk49_0,X1)|~neq(X1,nil)|~ssList(X1)),inference(split_conjunct,[status(thm)],[571])).
% cnf(581,negated_conjecture,(ssItem(esk52_0)|nil=esk51_0),inference(split_conjunct,[status(thm)],[571])).
% cnf(582,negated_conjecture,(ssList(esk53_0)|nil=esk50_0),inference(split_conjunct,[status(thm)],[571])).
% cnf(584,negated_conjecture,(ssList(esk54_0)|nil=esk50_0),inference(split_conjunct,[status(thm)],[571])).
% cnf(586,negated_conjecture,(app(app(esk53_0,esk50_0),esk54_0)=esk51_0|nil=esk50_0),inference(split_conjunct,[status(thm)],[571])).
% cnf(589,negated_conjecture,(cons(esk52_0,nil)=esk50_0|nil=esk51_0),inference(split_conjunct,[status(thm)],[571])).
% cnf(594,negated_conjecture,(esk50_0!=nil|esk49_0!=nil),inference(rw,[status(thm)],[576,577,theory(equality)])).
% cnf(595,negated_conjecture,(esk50_0!=nil|esk51_0!=nil),inference(rw,[status(thm)],[594,578,theory(equality)])).
% cnf(596,negated_conjecture,(ssList(esk50_0)),inference(rw,[status(thm)],[572,577,theory(equality)])).
% cnf(597,negated_conjecture,(ssList(esk51_0)),inference(rw,[status(thm)],[573,578,theory(equality)])).
% cnf(604,negated_conjecture,(esk51_0=nil|esk50_0!=nil|~ssList(nil)|~ssItem(esk52_0)),inference(spm,[status(thm)],[163,589,theory(equality)])).
% cnf(607,negated_conjecture,(esk51_0=nil|esk50_0!=nil|$false|~ssItem(esk52_0)),inference(rw,[status(thm)],[604,142,theory(equality)])).
% cnf(608,negated_conjecture,(esk51_0=nil|esk50_0!=nil|~ssItem(esk52_0)),inference(cn,[status(thm)],[607,theory(equality)])).
% cnf(623,negated_conjecture,(~ssList(X1)|~neq(X1,nil)|~segmentP(esk50_0,X1)|~segmentP(esk49_0,X1)),inference(rw,[status(thm)],[579,577,theory(equality)])).
% cnf(624,negated_conjecture,(~ssList(X1)|~neq(X1,nil)|~segmentP(esk50_0,X1)|~segmentP(esk51_0,X1)),inference(rw,[status(thm)],[623,578,theory(equality)])).
% cnf(626,negated_conjecture,(~segmentP(esk51_0,esk50_0)|~ssList(esk50_0)|~neq(esk50_0,nil)),inference(spm,[status(thm)],[624,210,theory(equality)])).
% cnf(630,negated_conjecture,(~segmentP(esk51_0,esk50_0)|$false|~neq(esk50_0,nil)),inference(rw,[status(thm)],[626,596,theory(equality)])).
% cnf(631,negated_conjecture,(~segmentP(esk51_0,esk50_0)|~neq(esk50_0,nil)),inference(cn,[status(thm)],[630,theory(equality)])).
% cnf(1555,negated_conjecture,(esk51_0=nil|esk50_0!=nil),inference(csr,[status(thm)],[608,581])).
% cnf(1556,negated_conjecture,(esk50_0!=nil),inference(csr,[status(thm)],[1555,595])).
% cnf(1558,negated_conjecture,(ssList(esk53_0)),inference(sr,[status(thm)],[582,1556,theory(equality)])).
% cnf(1559,negated_conjecture,(ssList(esk54_0)),inference(sr,[status(thm)],[584,1556,theory(equality)])).
% cnf(1561,negated_conjecture,(app(app(esk53_0,esk50_0),esk54_0)=esk51_0),inference(sr,[status(thm)],[586,1556,theory(equality)])).
% cnf(1719,negated_conjecture,(segmentP(X1,esk50_0)|esk51_0!=X1|~ssList(esk54_0)|~ssList(esk53_0)|~ssList(esk50_0)|~ssList(X1)),inference(spm,[status(thm)],[131,1561,theory(equality)])).
% cnf(1753,negated_conjecture,(segmentP(X1,esk50_0)|esk51_0!=X1|$false|~ssList(esk53_0)|~ssList(esk50_0)|~ssList(X1)),inference(rw,[status(thm)],[1719,1559,theory(equality)])).
% cnf(1754,negated_conjecture,(segmentP(X1,esk50_0)|esk51_0!=X1|$false|$false|~ssList(esk50_0)|~ssList(X1)),inference(rw,[status(thm)],[1753,1558,theory(equality)])).
% cnf(1755,negated_conjecture,(segmentP(X1,esk50_0)|esk51_0!=X1|$false|$false|$false|~ssList(X1)),inference(rw,[status(thm)],[1754,596,theory(equality)])).
% cnf(1756,negated_conjecture,(segmentP(X1,esk50_0)|esk51_0!=X1|~ssList(X1)),inference(cn,[status(thm)],[1755,theory(equality)])).
% cnf(2209,negated_conjecture,(segmentP(esk51_0,esk50_0)|~ssList(esk51_0)),inference(er,[status(thm)],[1756,theory(equality)])).
% cnf(2210,negated_conjecture,(segmentP(esk51_0,esk50_0)|$false),inference(rw,[status(thm)],[2209,597,theory(equality)])).
% cnf(2211,negated_conjecture,(segmentP(esk51_0,esk50_0)),inference(cn,[status(thm)],[2210,theory(equality)])).
% cnf(2218,negated_conjecture,($false|~neq(esk50_0,nil)),inference(rw,[status(thm)],[631,2211,theory(equality)])).
% cnf(2219,negated_conjecture,(~neq(esk50_0,nil)),inference(cn,[status(thm)],[2218,theory(equality)])).
% cnf(2239,negated_conjecture,(esk50_0=nil|~ssList(nil)|~ssList(esk50_0)),inference(spm,[status(thm)],[2219,136,theory(equality)])).
% cnf(2241,negated_conjecture,(esk50_0=nil|$false|~ssList(esk50_0)),inference(rw,[status(thm)],[2239,142,theory(equality)])).
% cnf(2242,negated_conjecture,(esk50_0=nil|$false|$false),inference(rw,[status(thm)],[2241,596,theory(equality)])).
% cnf(2243,negated_conjecture,(esk50_0=nil),inference(cn,[status(thm)],[2242,theory(equality)])).
% cnf(2244,negated_conjecture,($false),inference(sr,[status(thm)],[2243,1556,theory(equality)])).
% cnf(2245,negated_conjecture,($false),2244,['proof']).
% # SZS output end CNFRefutation
% # Processed clauses : 273
% # ...of these trivial : 3
% # ...subsumed : 11
% # ...remaining for further processing: 259
% # Other redundant clauses eliminated : 69
% # Clauses deleted for lack of memory : 0
% # Backward-subsumed : 6
% # Backward-rewritten : 11
% # Generated clauses : 846
% # ...of the previous two non-trivial : 715
% # Contextual simplify-reflections : 5
% # Paramodulations : 748
% # Factorizations : 0
% # Equation resolutions : 93
% # Current number of processed clauses: 231
% # Positive orientable unit clauses: 38
% # Positive unorientable unit clauses: 0
% # Negative unit clauses : 5
% # Non-unit-clauses : 188
% # Current number of unprocessed clauses: 497
% # ...number of literals in the above : 3427
% # Clause-clause subsumption calls (NU) : 943
% # Rec. Clause-clause subsumption calls : 221
% # Unit Clause-clause subsumption calls : 129
% # Rewrite failures with RHS unbound : 0
% # Indexed BW rewrite attempts : 11
% # Indexed BW rewrite successes : 11
% # Backwards rewriting index: 268 leaves, 1.30+/-1.066 terms/leaf
% # Paramod-from index: 123 leaves, 1.00+/-0.000 terms/leaf
% # Paramod-into index: 226 leaves, 1.21+/-0.920 terms/leaf
% # -------------------------------------------------
% # User time : 0.082 s
% # System time : 0.003 s
% # Total time : 0.085 s
% # Maximum resident set size: 0 pages
% PrfWatch: 0.22 CPU 0.30 WC
% FINAL PrfWatch: 0.22 CPU 0.30 WC
% SZS output end Solution for /tmp/SystemOnTPTP17253/SWC071+1.tptp
%
%------------------------------------------------------------------------------