lp_heuristic.h

#ifndef PROBFD_HEURISTICS_LP_HEURISTIC_H
#define PROBFD_HEURISTICS_LP_HEURISTIC_H
 
#include "probfd/heuristics/task_dependent_heuristic.h"
 
#include "downward/lp/lp_solver.h"
 
#include <memory>
#include <vector>
 
namespace probfd::heuristics {
 
template <typename Derived>
class LPHeuristic : public TaskDependentHeuristic {
protected:
    mutable lp::LPSolver lp_solver_;
 
public:
    LPHeuristic(
        std::shared_ptr<ProbabilisticTask> task,
        utils::LogProxy log,
        lp::LPSolverType solver_type)
        : TaskDependentHeuristic(task, log)
        , lp_solver_(solver_type)
    {
    }
 
    value_t evaluate(const State& state) const final
    {
        assert(!lp_solver_.has_temporary_constraints());
 
        static_cast<const Derived*>(this)->update_constraints(state);
 
        lp_solver_.solve();
 
        value_t result = lp_solver_.has_optimal_solution()
                             ? lp_solver_.get_objective_value()
                             : INFINITE_VALUE;
 
        lp_solver_.clear_temporary_constraints();
        static_cast<const Derived*>(this)->reset_constraints(state);
 
        return result;
    }
};
 
} // namespace probfd::heuristics
 
#endif