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+/*********************                                                        */
+/*! \file simplex.h
+ ** \verbatim
+ ** Original author: taking
+ ** Major contributors: none
+ ** Minor contributors (to current version): kshitij, mdeters
+ ** This file is part of the CVC4 prototype.
+ ** Copyright (c) 2009-2012  New York University and The University of Iowa
+ ** See the file COPYING in the top-level source directory for licensing
+ ** information.\endverbatim
+ **
+ ** \brief This is an implementation of the Simplex Module for the Simplex for DPLL(T)
+ ** decision procedure.
+ **
+ ** This implements the Simplex module for the Simpelx for DPLL(T) decision procedure.
+ ** See the Simplex for DPLL(T) technical report for more background.(citation?)
+ ** This shares with the theory a Tableau, and a PartialModel that:
+ **  - satisfies the equalities in the Tableau, and
+ **  - the assignment for the non-basic variables satisfies their bounds.
+ ** This is required to either produce a conflict or satisifying PartialModel.
+ ** Further, we require being told when a basic variable updates its value.
+ **
+ ** During the Simplex search we maintain a queue of variables.
+ ** The queue is required to contain all of the basic variables that voilate their bounds.
+ ** As elimination from the queue is more efficient to be done lazily,
+ ** we do not maintain that the queue of variables needs to be only basic variables or only
+ ** variables that satisfy their bounds.
+ **
+ ** The simplex procedure roughly follows Alberto's thesis. (citation?)
+ ** There is one round of selecting using a heuristic pivoting rule. (See PreferenceFunction
+ ** Documentation for the available options.)
+ ** The non-basic variable is the one that appears in the fewest pivots. (Bruno says that
+ ** Leonardo invented this first.)
+ ** After this, Bland's pivot rule is invoked.
+ **
+ ** During this proccess, we periodically inspect the queue of variables to
+ ** 1) remove now extraneous extries,
+ ** 2) detect conflicts that are "waiting" on the queue but may not be detected by the
+ **  current queue heuristics, and
+ ** 3) detect multiple conflicts.
+ **
+ ** Conflicts are greedily slackened to use the weakest bounds that still produce the
+ ** conflict.
+ **
+ ** Extra things tracked atm: (Subject to change at Tim's whims)
+ ** - A superset of all of the newly pivoted variables.
+ ** - A queue of additional conflicts that were discovered by Simplex.
+ **   These are theory valid and are currently turned into lemmas
+ **/
+
+
+#include "cvc4_private.h"
+
+#pragma once
+
+#include "util/statistics_registry.h"
+#include "theory/arith/simplex.h"
+#include "theory/arith/approx_simplex.h"
+
+namespace CVC4 {
+namespace theory {
+namespace arith {
+
+class AttemptSolutionSDP : public SimplexDecisionProcedure {
+public:
+  AttemptSolutionSDP(LinearEqualityModule& linEq, ErrorSet& errors, RaiseConflict conflictChannel, TempVarMalloc tvmalloc);
+
+  Result::Sat attempt(const ApproximateSimplex::Solution& sol);
+
+  Result::Sat findModel(bool exactResult){
+    Unreachable();
+  }
+
+private:
+  bool matchesNewValue(const DenseMap<DeltaRational>& nv, ArithVar v) const;
+
+  bool processSignals(){
+    TimerStat &timer = d_statistics.d_queueTime;
+    IntStat& conflictStat  = d_statistics.d_conflicts;
+    return standardProcessSignals(timer, conflictStat);
+  }
+  /** These fields are designed to be accessible to TheoryArith methods. */
+  class Statistics {
+  public:
+    TimerStat d_searchTime;
+    TimerStat d_queueTime;
+    IntStat d_conflicts;
+
+    Statistics();
+    ~Statistics();
+  } d_statistics;
+};/* class AttemptSolutionSDP */
+
+}/* CVC4::theory::arith namespace */
+}/* CVC4::theory namespace */
+}/* CVC4 namespace */
+