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diff --git a/src/proof/dimacs_printer.cpp b/src/proof/dimacs_printer.cpp
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+/*********************                                                        */
+/*! \file dimacs_printer.cpp
+ ** \verbatim
+ ** Top contributors (to current version):
+ **   Alex Ozdemir
+ ** This file is part of the CVC4 project.
+ ** Copyright (c) 2009-2018 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_printer.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::vector<std::pair<ClauseId, prop::SatClause>>& usedClauses)
+{
+  size_t maxVar = 0;
+  for (const auto& c : usedClauses)
+  {
+    for (const auto& l : c.second)
+    {
+      if (l.getSatVariable() + 1 > maxVar)
+      {
+        maxVar = l.getSatVariable() + 1;
+      }
+    }
+  }
+  o << "p cnf " << maxVar << " " << usedClauses.size() << '\n';
+  for (const auto& idAndClause : usedClauses)
+  {
+    for (const auto& l : idAndClause.second)
+    {
+      if (l.isNegated())
+      {
+        o << '-';
+      }
+      o << l.getSatVariable() + 1 << " ";
+    }
+    o << "0\n";
+  }
+}
+
+}  // namespace proof
+}  // namespace CVC4