text: //===-- Solution.h ------- PBQP Solution ------------------------*- C++ -*-===//
  //
  //                     The LLVM Compiler Infrastructure
  //
  // This file is distributed under the University of Illinois Open Source
  // License. See LICENSE.TXT for details.
  //
  //===----------------------------------------------------------------------===//
  //
  // PBQP Solution class.
  //
  //===----------------------------------------------------------------------===//
  
  #ifndef LLVM_CODEGEN_PBQP_SOLUTION_H
  #define LLVM_CODEGEN_PBQP_SOLUTION_H
  
  #include "Graph.h"
  #include "Math.h"
  #include <map>
  
  namespace PBQP {
  
    /// \brief Represents a solution to a PBQP problem.
    ///
    /// To get the selection for each node in the problem use the getSelection method.
    class Solution {
    private:
  
      typedef std::map<GraphBase::NodeId, unsigned> SelectionsMap;
      SelectionsMap selections;
  
      unsigned r0Reductions, r1Reductions, r2Reductions, rNReductions;
  
    public:
  
      /// \brief Initialise an empty solution.
      Solution()
        : r0Reductions(0), r1Reductions(0), r2Reductions(0), rNReductions(0) {}
  
      /// \brief Number of nodes for which selections have been made.
      /// @return Number of nodes for which selections have been made.
      unsigned numNodes() const { return selections.size(); }
  
      /// \brief Records a reduction via the R0 rule. Should be called from the
      ///        solver only.
      void recordR0() { ++r0Reductions; }
  
      /// \brief Returns the number of R0 reductions applied to solve the problem.
      unsigned numR0Reductions() const { return r0Reductions; }
  
      /// \brief Records a reduction via the R1 rule. Should be called from the
      ///        solver only.
      void recordR1() { ++r1Reductions; }
  
      /// \brief Returns the number of R1 reductions applied to solve the problem.
      unsigned numR1Reductions() const { return r1Reductions; }
  
      /// \brief Records a reduction via the R2 rule. Should be called from the
      ///        solver only.
      void recordR2() { ++r2Reductions; }
  
      /// \brief Returns the number of R2 reductions applied to solve the problem.
      unsigned numR2Reductions() const { return r2Reductions; }
  
      /// \brief Records a reduction via the RN rule. Should be called from the
      ///        solver only.
      void recordRN() { ++ rNReductions; }
  
      /// \brief Returns the number of RN reductions applied to solve the problem.
      unsigned numRNReductions() const { return rNReductions; }
  
      /// \brief Set the selection for a given node.
      /// @param nodeId Node id.
      /// @param selection Selection for nodeId.
      void setSelection(GraphBase::NodeId nodeId, unsigned selection) {
        selections[nodeId] = selection;
      }
  
      /// \brief Get a node's selection.
      /// @param nodeId Node id.
      /// @return The selection for nodeId;
      unsigned getSelection(GraphBase::NodeId nodeId) const {
        SelectionsMap::const_iterator sItr = selections.find(nodeId);
        assert(sItr != selections.end() && "No selection for node.");
        return sItr->second;
      }
  
    };
  
  }
  
  #endif // LLVM_CODEGEN_PBQP_SOLUTION_H
  