/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* */ /* This file is part of the program and library */ /* SCIP --- Solving Constraint Integer Programs */ /* */ /* Copyright 2002-2022 Zuse Institute Berlin */ /* */ /* Licensed under the Apache License, Version 2.0 (the "License"); */ /* you may not use this file except in compliance with the License. */ /* You may obtain a copy of the License at */ /* */ /* http://www.apache.org/licenses/LICENSE-2.0 */ /* */ /* Unless required by applicable law or agreed to in writing, software */ /* distributed under the License is distributed on an "AS IS" BASIS, */ /* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. */ /* See the License for the specific language governing permissions and */ /* limitations under the License. */ /* */ /* You should have received a copy of the Apache-2.0 license */ /* along with SCIP; see the file LICENSE. If not visit scipopt.org. */ /* */ /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /**@file scip_tree.h * @ingroup PUBLICCOREAPI * @brief public methods for the branch-and-bound tree * @author Tobias Achterberg * @author Timo Berthold * @author Thorsten Koch * @author Alexander Martin * @author Marc Pfetsch * @author Kati Wolter * @author Gregor Hendel * @author Leona Gottwald */ /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/ #ifndef __SCIP_SCIP_TREE_H__ #define __SCIP_SCIP_TREE_H__ #include "scip/def.h" #include "scip/type_retcode.h" #include "scip/type_scip.h" #include "scip/type_tree.h" #ifdef __cplusplus extern "C" { #endif /**@addtogroup PublicTreeMethods * * @{ */ /** gets focus node in the tree * * if we are in probing/diving mode this method returns the node in the tree where the probing/diving mode was started. * * @return the current node of the search tree * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_INITPRESOLVE * - \ref SCIP_STAGE_PRESOLVING * - \ref SCIP_STAGE_EXITPRESOLVE * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_NODE* SCIPgetFocusNode( SCIP* scip /**< SCIP data structure */ ); /** gets current node in the tree * * @return the current node of the search tree * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_INITPRESOLVE * - \ref SCIP_STAGE_PRESOLVING * - \ref SCIP_STAGE_EXITPRESOLVE * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_NODE* SCIPgetCurrentNode( SCIP* scip /**< SCIP data structure */ ); /** gets depth of current node, or -1 if no current node exists; in probing, the current node is the last probing node, * such that the depth includes the probing path * * @return the depth of current node, or -1 if no current node exists; in probing, the current node is the last probing node, * such that the depth includes the probing path * * @pre This method can be called if SCIP is in one of the following stages: * - \ref SCIP_STAGE_TRANSFORMED * - \ref SCIP_STAGE_INITPRESOLVE * - \ref SCIP_STAGE_PRESOLVING * - \ref SCIP_STAGE_EXITPRESOLVE * - \ref SCIP_STAGE_PRESOLVED * - \ref SCIP_STAGE_INITSOLVE * - \ref SCIP_STAGE_SOLVING * - \ref SCIP_STAGE_SOLVED * - \ref SCIP_STAGE_EXITSOLVE */ SCIP_EXPORT int SCIPgetDepth( SCIP* scip /**< SCIP data structure */ ); /** gets depth of the focus node, or -1 if no focus node exists; the focus node is the currently processed node in the * branching tree, excluding the nodes of the probing path * * @return the depth of the focus node, or -1 if no focus node exists; the focus node is the currently processed node in the * branching tree, excluding the nodes of the probing path * * @pre This method can be called if SCIP is in one of the following stages: * - \ref SCIP_STAGE_TRANSFORMED * - \ref SCIP_STAGE_INITPRESOLVE * - \ref SCIP_STAGE_PRESOLVING * - \ref SCIP_STAGE_EXITPRESOLVE * - \ref SCIP_STAGE_PRESOLVED * - \ref SCIP_STAGE_INITSOLVE * - \ref SCIP_STAGE_SOLVING * - \ref SCIP_STAGE_SOLVED * - \ref SCIP_STAGE_EXITSOLVE */ SCIP_EXPORT int SCIPgetFocusDepth( SCIP* scip /**< SCIP data structure */ ); /** gets current plunging depth (successive times, a child was selected as next node) * * @return the current plunging depth (successive times, a child was selected as next node) * * @pre This method can be called if SCIP is in one of the following stages: * - \ref SCIP_STAGE_PRESOLVED * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT int SCIPgetPlungeDepth( SCIP* scip /**< SCIP data structure */ ); /** gets the root node of the tree * * @return the root node of the search tree * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_INITPRESOLVE * - \ref SCIP_STAGE_PRESOLVING * - \ref SCIP_STAGE_EXITPRESOLVE * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_NODE* SCIPgetRootNode( SCIP* scip /**< SCIP data structure */ ); /** gets the effective root depth, i.e., the depth of the deepest node which is part of all paths from the root node * to the unprocessed nodes. * * @return effective root depth * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT int SCIPgetEffectiveRootDepth( SCIP* scip /**< SCIP data structure */ ); /** returns whether the current node is already solved and only propagated again * * @return TRUE is returned if \SCIP performance repropagation, otherwise FALSE. * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_INITPRESOLVE * - \ref SCIP_STAGE_PRESOLVING * - \ref SCIP_STAGE_EXITPRESOLVE * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_Bool SCIPinRepropagation( SCIP* scip /**< SCIP data structure */ ); /** gets children of focus node along with the number of children * * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes. * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_RETCODE SCIPgetChildren( SCIP* scip, /**< SCIP data structure */ SCIP_NODE*** children, /**< pointer to store children array, or NULL if not needed */ int* nchildren /**< pointer to store number of children, or NULL if not needed */ ); /** gets number of children of focus node * * @return number of children of the focus node * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT int SCIPgetNChildren( SCIP* scip /**< SCIP data structure */ ); /** gets siblings of focus node along with the number of siblings * * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes. * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_RETCODE SCIPgetSiblings( SCIP* scip, /**< SCIP data structure */ SCIP_NODE*** siblings, /**< pointer to store siblings array, or NULL if not needed */ int* nsiblings /**< pointer to store number of siblings, or NULL if not needed */ ); /** gets number of siblings of focus node * * @return the number of siblings of focus node * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT int SCIPgetNSiblings( SCIP* scip /**< SCIP data structure */ ); /** gets leaves of the tree along with the number of leaves * * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes. * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_RETCODE SCIPgetLeaves( SCIP* scip, /**< SCIP data structure */ SCIP_NODE*** leaves, /**< pointer to store leaves array, or NULL if not needed */ int* nleaves /**< pointer to store number of leaves, or NULL if not needed */ ); /** gets number of leaves in the tree * * @return the number of leaves in the tree * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT int SCIPgetNLeaves( SCIP* scip /**< SCIP data structure */ ); /** gets number of nodes left in the tree (children + siblings + leaves) * * @return the number of nodes left in the tree (children + siblings + leaves) * * @pre This method can be called if SCIP is in one of the following stages: * - \ref SCIP_STAGE_PRESOLVED * - \ref SCIP_STAGE_SOLVING * - \ref SCIP_STAGE_SOLVED */ SCIP_EXPORT int SCIPgetNNodesLeft( SCIP* scip /**< SCIP data structure */ ); /** gets the best child of the focus node w.r.t. the node selection priority assigned by the branching rule * * @return the best child of the focus node w.r.t. the node selection priority assigned by the branching rule * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_NODE* SCIPgetPrioChild( SCIP* scip /**< SCIP data structure */ ); /** gets the best sibling of the focus node w.r.t. the node selection priority assigned by the branching rule * * @return the best sibling of the focus node w.r.t. the node selection priority assigned by the branching rule * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_NODE* SCIPgetPrioSibling( SCIP* scip /**< SCIP data structure */ ); /** gets the best child of the focus node w.r.t. the node selection strategy * * @return the best child of the focus node w.r.t. the node selection strategy * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_NODE* SCIPgetBestChild( SCIP* scip /**< SCIP data structure */ ); /** gets the best sibling of the focus node w.r.t. the node selection strategy * * @return the best sibling of the focus node w.r.t. the node selection strategy * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_NODE* SCIPgetBestSibling( SCIP* scip /**< SCIP data structure */ ); /** gets the best leaf from the node queue w.r.t. the node selection strategy * * @return the best leaf from the node queue w.r.t. the node selection strategy * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_NODE* SCIPgetBestLeaf( SCIP* scip /**< SCIP data structure */ ); /** gets the best node from the tree (child, sibling, or leaf) w.r.t. the node selection strategy * * @return the best node from the tree (child, sibling, or leaf) w.r.t. the node selection strategy * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_NODE* SCIPgetBestNode( SCIP* scip /**< SCIP data structure */ ); /** gets the node with smallest lower bound from the tree (child, sibling, or leaf) * * @return the node with smallest lower bound from the tree (child, sibling, or leaf) * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_NODE* SCIPgetBestboundNode( SCIP* scip /**< SCIP data structure */ ); /** access to all data of open nodes (leaves, children, and siblings) * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_RETCODE SCIPgetOpenNodesData( SCIP* scip, /**< SCIP data structure */ SCIP_NODE*** leaves, /**< pointer to store the leaves, or NULL if not needed */ SCIP_NODE*** children, /**< pointer to store the children, or NULL if not needed */ SCIP_NODE*** siblings, /**< pointer to store the siblings, or NULL if not needed */ int* nleaves, /**< pointer to store the number of leaves, or NULL */ int* nchildren, /**< pointer to store the number of children, or NULL */ int* nsiblings /**< pointer to store the number of siblings, or NULL */ ); /** marks node and whole sub tree to be cut off from branch and bound tree * * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes. * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_RETCODE SCIPcutoffNode( SCIP* scip, /**< SCIP data structure */ SCIP_NODE* node /**< node that should be cut off */ ); /** removes all nodes from branch and bound tree that were marked to be cut off via SCIPcutoffNode() * * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes. * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING * * @note In diving mode, the removal of nodes is delayed until diving ends. */ SCIP_EXPORT SCIP_RETCODE SCIPpruneTree( SCIP* scip /**< SCIP data structure */ ); /** marks the given node to be propagated again the next time a node of its subtree is processed * * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes. * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_RETCODE SCIPrepropagateNode( SCIP* scip, /**< SCIP data structure */ SCIP_NODE* node /**< node that should be propagated again */ ); /** returns depth of first node in active path that is marked being cutoff * * @return depth of first node in active path that is marked being cutoff * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT int SCIPgetCutoffdepth( SCIP* scip /**< SCIP data structure */ ); /** returns depth of first node in active path that has to be propagated again * * @return depth of first node in active path that has to be propagated again * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT int SCIPgetRepropdepth( SCIP* scip /**< SCIP data structure */ ); /** prints all branching decisions on variables from the root to the given node * * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes. * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT SCIP_RETCODE SCIPprintNodeRootPath( SCIP* scip, /**< SCIP data structure */ SCIP_NODE* node, /**< node data */ FILE* file /**< output file (or NULL for standard output) */ ); /** sets whether the LP should be solved at the focus node * * @note In order to have an effect, this method needs to be called after a node is focused but before the LP is * solved. * * @pre This method can be called if @p scip is in one of the following stages: * - \ref SCIP_STAGE_SOLVING */ SCIP_EXPORT void SCIPsetFocusnodeLP( SCIP* scip, /**< SCIP data structure */ SCIP_Bool solvelp /**< should the LP be solved? */ ); /** query if node was the last parent of a branching of the tree * * @return TRUE if node was the last parent of a branching of the tree * * @pre This method can be called if SCIP is in one of the following stages: * - \ref SCIP_STAGE_PRESOLVED * - \ref SCIP_STAGE_SOLVING * - \ref SCIP_STAGE_SOLVED */ SCIP_EXPORT SCIP_Bool SCIPwasNodeLastBranchParent( SCIP* scip, /**< SCIP data structure */ SCIP_NODE* node /**< tree node, or NULL to check focus node */ ); /**@} */ #ifdef __cplusplus } #endif #endif