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diff --git a/src/proof/dimacs.cpp b/src/proof/dimacs.cpp
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+/*********************                                                        */
+/*! \file dimacs.cpp
+ ** \verbatim
+ ** Top contributors (to current version):
+ **   Alex Ozdemir
+ ** This file is part of the CVC4 project.
+ ** Copyright (c) 2009-2019 by the authors listed in the file AUTHORS
+ ** in the top-level source directory) and their institutional affiliations.
+ ** All rights reserved.  See the file COPYING in the top-level source
+ ** directory for licensing information.\endverbatim
+ **
+ ** \brief DIMACS SAT Problem Format
+ **
+ ** Defines serialization for SAT problems as DIMACS
+ **/
+
+#include "proof/dimacs.h"
+
+#include "base/cvc4_assert.h"
+
+#include <iostream>
+
+namespace CVC4 {
+namespace proof {
+
+// Prints the literal as a (+) or (-) int
+// Not operator<< b/c that represents negation as ~
+std::ostream& textOut(std::ostream& o, const prop::SatLiteral& l)
+{
+  if (l.isNegated())
+  {
+    o << "-";
+  }
+  return o << l.getSatVariable() + 1;
+}
+
+// Prints the clause as a space-separated list of ints
+// Not operator<< b/c that represents negation as ~
+std::ostream& textOut(std::ostream& o, const prop::SatClause& c)
+{
+  for (const auto& l : c)
+  {
+    textOut(o, l) << " ";
+  }
+  return o << "0";
+}
+
+void printDimacs(std::ostream& o,
+                 const std::unordered_map<ClauseId, prop::SatClause>& clauses,
+                 const std::vector<ClauseId>& usedIndices)
+{
+  size_t maxVar = 0;
+  for (const ClauseId i : usedIndices)
+  {
+    const prop::SatClause& c = clauses.at(i);
+    for (const auto& l : c)
+    {
+      if (l.getSatVariable() + 1 > maxVar)
+      {
+        maxVar = l.getSatVariable() + 1;
+      }
+    }
+  }
+  o << "p cnf " << maxVar << " " << usedIndices.size() << '\n';
+  for (const ClauseId i : usedIndices)
+  {
+    const prop::SatClause& c = clauses.at(i);
+    for (const auto& l : c)
+    {
+      if (l.isNegated())
+      {
+        o << '-';
+      }
+      o << l.getSatVariable() + 1 << " ";
+    }
+    o << "0\n";
+  }
+}
+
+std::vector<prop::SatClause> parseDimacs(std::istream& in)
+{
+  std::string tag;
+  uint64_t nVars;
+  uint64_t nClauses;
+
+  in >> tag;
+  Assert(in.good());
+  Assert(tag == "p");
+
+  in >> tag;
+  Assert(in.good());
+  Assert(tag == "cnf");
+
+  in >> nVars;
+  Assert(nVars >= 0);
+
+  in >> nClauses;
+  Assert(nClauses >= 0);
+
+  std::vector<prop::SatClause> cnf;
+  for (uint64_t i = 0; i < nClauses; ++i)
+  {
+    cnf.emplace_back();
+    int64_t lit;
+    in >> lit;
+    Assert(in.good());
+    while (lit != 0)
+    {
+      cnf.back().emplace_back(std::abs(lit) - 1, lit < 0);
+      in >> lit;
+      Assert(static_cast<uint64_t>(std::abs(lit)) <= nVars);
+      Assert(in.good());
+    }
+  }
+
+  return cnf;
+}
+
+}  // namespace proof
+}  // namespace CVC4