branch_node.hpp

Go to the documentation of this file.

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#ifndef CMR_BRANCH_NODE_H
#define CMR_BRANCH_NODE_H

#include "lp_util.hpp"
#include "util.hpp"

#include <array>
#include <iostream>
#include <list>
#include <utility>


namespace CMR {
namespace ABC {

struct BranchNode {
    enum Dir : int {
        Down = 0,
        Up = 1
    };

    enum class Status {
        NeedsCut,
        NeedsBranch,
        NeedsPrice,
        NeedsRecover,
        Pruned,
        Done,
    };

    BranchNode(); 

    BranchNode(EndPts ends_, Dir direction_, const BranchNode &parent_,
               double tourlen_, double estimate_);

    BranchNode(BranchNode &&B) noexcept;
    BranchNode &operator=(BranchNode &&B) noexcept;

    using Split = std::array<BranchNode, 2>;

    EndPts ends; 
    Dir direction; 

    Status stat; 

    const BranchNode *parent;
    int depth; 

    double tourlen; 

    LP::Basis::Ptr price_basis;
    double estimate; 

    bool is_root() const { return parent == nullptr; }

    bool visited() const
        { return stat == Status::Pruned || stat == Status::Done; }


    static bool tour_worse(const std::list<BranchNode>::iterator &A,
                           const std::list<BranchNode>::iterator &B);

    static bool bound_worse(const std::list<BranchNode>::iterator &A,
                            const std::list<BranchNode>::iterator &B);

    using Pref = decltype(&tour_worse);

};

BranchNode::Dir dir_from_int(int entry);

std::string bnode_brief(const BranchNode &B);

std::ostream &operator<<(std::ostream &os, const BranchNode::Dir &dir);
std::ostream &operator<<(std::ostream &os, const BranchNode &B);

using BranchHistory = std::list<BranchNode>;

using EndsDir = std::pair<EndPts, BranchNode::Dir>;




}
}

#endif