1    	/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2    	/*                                                                           */
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4    	/*         SCIP --- Solving Constraint Integer Programs                      */
5    	/*                                                                           */
6    	/*  Copyright (c) 2002-2023 Zuse Institute Berlin (ZIB)                      */
7    	/*                                                                           */
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13   	/*                                                                           */
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22   	/*                                                                           */
23   	/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24   	
25   	/**@file   nodesel.h
26   	 * @ingroup INTERNALAPI
27   	 * @brief  internal methods for node selectors and node priority queues
28   	 * @author Tobias Achterberg
29   	 */
30   	
31   	/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
32   	
33   	#ifndef __SCIP_NODESEL_H__
34   	#define __SCIP_NODESEL_H__
35   	
36   	
37   	#include "scip/def.h"
38   	#include "blockmemshell/memory.h"
39   	#include "scip/type_event.h"
40   	#include "scip/type_retcode.h"
41   	#include "scip/type_set.h"
42   	#include "scip/type_stat.h"
43   	#include "scip/type_lp.h"
44   	#include "scip/type_tree.h"
45   	#include "scip/type_reopt.h"
46   	#include "scip/pub_nodesel.h"
47   	
48   	#ifdef __cplusplus
49   	extern "C" {
50   	#endif
51   	
52   	/* 
53   	 * node priority queue methods
54   	 */
55   	
56   	/** creates node priority queue */
57   	SCIP_RETCODE SCIPnodepqCreate(
58   	   SCIP_NODEPQ**         nodepq,             /**< pointer to a node priority queue */
59   	   SCIP_SET*             set,                /**< global SCIP settings */
60   	   SCIP_NODESEL*         nodesel             /**< node selector to use for sorting the nodes in the queue */
61   	   );
62   	
63   	/** frees node priority queue, but not the data nodes themselves */
64   	void SCIPnodepqDestroy(
65   	   SCIP_NODEPQ**         nodepq              /**< pointer to a node priority queue */
66   	   );
67   	
68   	/** frees node priority queue and all nodes in the queue */
69   	SCIP_RETCODE SCIPnodepqFree(
70   	   SCIP_NODEPQ**         nodepq,             /**< pointer to a node priority queue */
71   	   BMS_BLKMEM*           blkmem,             /**< block memory buffers */
72   	   SCIP_SET*             set,                /**< global SCIP settings */
73   	   SCIP_STAT*            stat,               /**< problem statistics */
74   	   SCIP_EVENTFILTER*     eventfilter,        /**< event filter for global (not variable dependent) events */
75   	   SCIP_EVENTQUEUE*      eventqueue,         /**< event queue */
76   	   SCIP_TREE*            tree,               /**< branch and bound tree */
77   	   SCIP_LP*              lp                  /**< current LP data */
78   	   );
79   	
80   	/** deletes all nodes in the node priority queue */
81   	SCIP_RETCODE SCIPnodepqClear(
82   	   SCIP_NODEPQ*          nodepq,             /**< node priority queue */
83   	   BMS_BLKMEM*           blkmem,             /**< block memory buffers */
84   	   SCIP_SET*             set,                /**< global SCIP settings */
85   	   SCIP_STAT*            stat,               /**< problem statistics */
86   	   SCIP_EVENTFILTER*     eventfilter,        /**< event filter for global (not variable dependent) events */
87   	   SCIP_EVENTQUEUE*      eventqueue,         /**< event queue */
88   	   SCIP_TREE*            tree,               /**< branch and bound tree */
89   	   SCIP_LP*              lp                  /**< current LP data */
90   	   );
91   	
92   	/** returns the node selector associated with the given node priority queue */
93   	SCIP_NODESEL* SCIPnodepqGetNodesel(
94   	   SCIP_NODEPQ*          nodepq              /**< node priority queue */
95   	   );
96   	
97   	/** sets the node selector used for sorting the nodes in the queue, and resorts the queue if necessary */
98   	SCIP_RETCODE SCIPnodepqSetNodesel(
99   	   SCIP_NODEPQ**         nodepq,             /**< pointer to a node priority queue */
100  	   SCIP_SET*             set,                /**< global SCIP settings */
101  	   SCIP_NODESEL*         nodesel             /**< node selector to use for sorting the nodes in the queue */
102  	   );
103  	
104  	/** compares two nodes; returns -1/0/+1 if node1 better/equal/worse than node2 */
105  	int SCIPnodepqCompare(
106  	   SCIP_NODEPQ*          nodepq,             /**< node priority queue */
107  	   SCIP_SET*             set,                /**< global SCIP settings */
108  	   SCIP_NODE*            node1,              /**< first node to compare */
109  	   SCIP_NODE*            node2               /**< second node to compare */
110  	   );
111  	
112  	/** inserts node into node priority queue */
113  	SCIP_RETCODE SCIPnodepqInsert(
114  	   SCIP_NODEPQ*          nodepq,             /**< node priority queue */
115  	   SCIP_SET*             set,                /**< global SCIP settings */
116  	   SCIP_NODE*            node                /**< node to be inserted */
117  	   );
118  	
119  	/** removes node from the node priority queue */
120  	SCIP_RETCODE SCIPnodepqRemove(
121  	   SCIP_NODEPQ*          nodepq,             /**< node priority queue */
122  	   SCIP_SET*             set,                /**< global SCIP settings */
123  	   SCIP_NODE*            node                /**< node to remove */
124  	   );
125  	
126  	/** returns the best node of the queue without removing it */
127  	SCIP_NODE* SCIPnodepqFirst(
128  	   const SCIP_NODEPQ*    nodepq              /**< node priority queue */
129  	   );
130  	
131  	/** returns the nodes array of the queue */
132  	SCIP_NODE** SCIPnodepqNodes(
133  	   const SCIP_NODEPQ*    nodepq              /**< node priority queue */
134  	   );
135  	
136  	/** returns the number of nodes stored in the node priority queue */
137  	int SCIPnodepqLen(
138  	   const SCIP_NODEPQ*    nodepq              /**< node priority queue */
139  	   );
140  	
141  	/** gets the minimal lower bound of all nodes in the queue */
142  	SCIP_Real SCIPnodepqGetLowerbound(
143  	   SCIP_NODEPQ*          nodepq,             /**< node priority queue */
144  	   SCIP_SET*             set                 /**< global SCIP settings */
145  	   );
146  	
147  	/** gets the node with minimal lower bound of all nodes in the queue */
148  	SCIP_NODE* SCIPnodepqGetLowerboundNode(
149  	   SCIP_NODEPQ*          nodepq,             /**< node priority queue */
150  	   SCIP_SET*             set                 /**< global SCIP settings */
151  	   );
152  	
153  	/** gets the sum of lower bounds of all nodes in the queue */
154  	SCIP_Real SCIPnodepqGetLowerboundSum(
155  	   SCIP_NODEPQ*          nodepq              /**< node priority queue */
156  	   );
157  	
158  	/** free all nodes from the queue that are cut off by the given upper bound */
159  	SCIP_RETCODE SCIPnodepqBound(
160  	   SCIP_NODEPQ*          nodepq,             /**< node priority queue */
161  	   BMS_BLKMEM*           blkmem,             /**< block memory buffer */
162  	   SCIP_SET*             set,                /**< global SCIP settings */
163  	   SCIP_STAT*            stat,               /**< dynamic problem statistics */
164  	   SCIP_EVENTFILTER*     eventfilter,        /**< event filter for global (not variable dependent) events */
165  	   SCIP_EVENTQUEUE*      eventqueue,         /**< event queue */
166  	   SCIP_TREE*            tree,               /**< branch and bound tree */
167  	   SCIP_REOPT*           reopt,              /**< reoptimization data structure */
168  	   SCIP_LP*              lp,                 /**< current LP data */
169  	   SCIP_Real             cutoffbound         /**< cutoff bound: all nodes with lowerbound >= cutoffbound are cut off */
170  	   );
171  	
172  	
173  	
174  	
175  	/*
176  	 * node selector methods
177  	 */
178  	
179  	/** copies the given node selector to a new scip */
180  	SCIP_RETCODE SCIPnodeselCopyInclude(
181  	   SCIP_NODESEL*         nodesel,            /**< node selector */
182  	   SCIP_SET*             set                 /**< SCIP_SET of SCIP to copy to */
183  	   );
184  	
185  	/** creates a node selector */
186  	SCIP_RETCODE SCIPnodeselCreate(
187  	   SCIP_NODESEL**        nodesel,            /**< pointer to store node selector */
188  	   SCIP_SET*             set,                /**< global SCIP settings */
189  	   SCIP_MESSAGEHDLR*     messagehdlr,        /**< message handler */
190  	   BMS_BLKMEM*           blkmem,             /**< block memory for parameter settings */
191  	   const char*           name,               /**< name of node selector */
192  	   const char*           desc,               /**< description of node selector */
193  	   int                   stdpriority,        /**< priority of the node selector in standard mode */
194  	   int                   memsavepriority,    /**< priority of the node selector in memory saving mode */
195  	   SCIP_DECL_NODESELCOPY ((*nodeselcopy)),   /**< copy method of node selector or NULL if you don't want to copy your plugin into sub-SCIPs */
196  	   SCIP_DECL_NODESELFREE ((*nodeselfree)),   /**< destructor of node selector */
197  	   SCIP_DECL_NODESELINIT ((*nodeselinit)),   /**< initialize node selector */
198  	   SCIP_DECL_NODESELEXIT ((*nodeselexit)),   /**< deinitialize node selector */
199  	   SCIP_DECL_NODESELINITSOL((*nodeselinitsol)),/**< solving process initialization method of node selector */
200  	   SCIP_DECL_NODESELEXITSOL((*nodeselexitsol)),/**< solving process deinitialization method of node selector */
201  	   SCIP_DECL_NODESELSELECT((*nodeselselect)),/**< node selection method */
202  	   SCIP_DECL_NODESELCOMP ((*nodeselcomp)),   /**< node comparison method */
203  	   SCIP_NODESELDATA*     nodeseldata         /**< node selector data */
204  	   );
205  	
206  	/** frees memory of node selector */
207  	SCIP_RETCODE SCIPnodeselFree(
208  	   SCIP_NODESEL**        nodesel,            /**< pointer to node selector data structure */
209  	   SCIP_SET*             set                 /**< global SCIP settings */
210  	   );
211  	
212  	/** initializes node selector */
213  	SCIP_RETCODE SCIPnodeselInit(
214  	   SCIP_NODESEL*         nodesel,            /**< node selector */
215  	   SCIP_SET*             set                 /**< global SCIP settings */
216  	   );
217  	
218  	/** deinitializes node selector */
219  	SCIP_RETCODE SCIPnodeselExit(
220  	   SCIP_NODESEL*         nodesel,            /**< node selector */
221  	   SCIP_SET*             set                 /**< global SCIP settings */
222  	   );
223  	
224  	/** informs node selector that the branch and bound process is being started */
225  	SCIP_RETCODE SCIPnodeselInitsol(
226  	   SCIP_NODESEL*         nodesel,            /**< node selector */
227  	   SCIP_SET*             set                 /**< global SCIP settings */
228  	   );
229  	
230  	/** informs node selector that the branch and bound process data is being freed */
231  	SCIP_RETCODE SCIPnodeselExitsol(
232  	   SCIP_NODESEL*         nodesel,            /**< node selector */
233  	   SCIP_SET*             set                 /**< global SCIP settings */
234  	   );
235  	
236  	/** select next node to be processed */
237  	SCIP_RETCODE SCIPnodeselSelect(
238  	   SCIP_NODESEL*         nodesel,            /**< node selector */
239  	   SCIP_SET*             set,                /**< global SCIP settings */
240  	   SCIP_NODE**           selnode             /**< pointer to store node to be processed next */
241  	   );
242  	
243  	/** compares two nodes; returns -1/0/+1 if node1 better/equal/worse than node2 */
244  	int SCIPnodeselCompare(
245  	   SCIP_NODESEL*         nodesel,            /**< node selector */
246  	   SCIP_SET*             set,                /**< global SCIP settings */
247  	   SCIP_NODE*            node1,              /**< first node to compare */
248  	   SCIP_NODE*            node2               /**< second node to compare */
249  	   );
250  	
251  	/** sets priority of node selector in standard mode */
252  	void SCIPnodeselSetStdPriority(
253  	   SCIP_NODESEL*         nodesel,            /**< node selector */
254  	   SCIP_SET*             set,                /**< global SCIP settings */
255  	   int                   priority            /**< new priority of the node selector */
256  	   );
257  	
258  	/** sets priority of node selector in memory saving mode */
259  	void SCIPnodeselSetMemsavePriority(
260  	   SCIP_NODESEL*         nodesel,            /**< node selector */
261  	   SCIP_SET*             set,                /**< global SCIP settings */
262  	   int                   priority            /**< new priority of the node selector */
263  	   );
264  	
265  	/** sets copy method of node selector */
266  	void SCIPnodeselSetCopy(
267  	   SCIP_NODESEL*         nodesel,            /**< node selector */
268  	   SCIP_DECL_NODESELCOPY ((*nodeselcopy))    /**< copy method of node selector or NULL if you don't want to copy your plugin into sub-SCIPs */
269  	   );
270  	
271  	/** sets destructor method of node selector */
272  	void SCIPnodeselSetFree(
273  	   SCIP_NODESEL*         nodesel,            /**< node selector */
274  	   SCIP_DECL_NODESELFREE ((*nodeselfree))    /**< destructor of node selector */
275  	   );
276  	
277  	/** sets initialization method of node selector */
278  	void SCIPnodeselSetInit(
279  	   SCIP_NODESEL*         nodesel,            /**< node selector */
280  	   SCIP_DECL_NODESELINIT ((*nodeselinit))    /**< initialize node selector */
281  	   );
282  	
283  	/** sets deinitialization method of node selector */
284  	void SCIPnodeselSetExit(
285  	   SCIP_NODESEL*         nodesel,            /**< node selector */
286  	   SCIP_DECL_NODESELEXIT ((*nodeselexit))    /**< deinitialize node selector */
287  	   );
288  	
289  	/** sets solving process initialization method of node selector */
290  	void SCIPnodeselSetInitsol(
291  	   SCIP_NODESEL*         nodesel,            /**< node selector */
292  	   SCIP_DECL_NODESELINITSOL ((*nodeselinitsol))/**< solving process initialization method of node selector */
293  	   );
294  	
295  	/** sets solving process deinitialization method of node selector */
296  	void SCIPnodeselSetExitsol(
297  	   SCIP_NODESEL*         nodesel,            /**< node selector */
298  	   SCIP_DECL_NODESELEXITSOL ((*nodeselexitsol))/**< solving process deinitialization method of node selector */
299  	   );
300  	
301  	/** enables or disables all clocks of \p nodesel, depending on the value of the flag */
302  	void SCIPnodeselEnableOrDisableClocks(
303  	   SCIP_NODESEL*         nodesel,            /**< the node selector for which all clocks should be enabled or disabled */
304  	   SCIP_Bool             enable              /**< should the clocks of the node selector be enabled? */
305  	   );
306  	
307  	#ifdef __cplusplus
308  	}
309  	#endif
310  	
311  	#endif
312