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4    	/*         SCIP --- Solving Constraint Integer Programs                      */
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24   	
25   	/**@file   cons_pseudoboolean.h
26   	 * @ingroup CONSHDLRS
27   	 * @brief  constraint handler for pseudoboolean constraints
28   	 * @author Stefan Heinz
29   	 * @author Michael Winkler
30   	 */
31   	
32   	/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
33   	
34   	#ifndef __SCIP_CONS_PSEUDOBOOLEAN_H__
35   	#define __SCIP_CONS_PSEUDOBOOLEAN_H__
36   	
37   	
38   	#include "scip/def.h"
39   	#include "scip/type_cons.h"
40   	#include "scip/type_retcode.h"
41   	#include "scip/type_scip.h"
42   	#include "scip/type_var.h"
43   	
44   	#ifdef __cplusplus
45   	extern "C" {
46   	#endif
47   	
48   	#define ARTIFICIALVARNAMEPREFIX "andresultant_"
49   	
50   	
51   	
52   	/** creates the handler for pseudoboolean constraints and includes it in SCIP
53   	 *
54   	 * @ingroup ConshdlrIncludes
55   	 * */
56   	SCIP_EXPORT
57   	SCIP_RETCODE SCIPincludeConshdlrPseudoboolean(
58   	   SCIP*                 scip                /**< SCIP data structure */
59   	   );
60   	
61   	/**@addtogroup CONSHDLRS
62   	 *
63   	 * @{
64   	 *
65   	 * @name Pseudoboolean Constraints
66   	 *
67   	 * @{
68   	 *
69   	 * The constraint handler deals with pseudo boolean constraints. These are constraints of the form
70   	 * \f[
71   	 * \mbox{lhs} \leq \sum_{k=0}^m c_k \cdot x_k  +  \sum_{i=0}^n c_i \cdot \prod_{j \in I_i} x_j \leq \mbox{rhs}
72   	 * \f]
73   	 * where all \f$x\f$ are binary.
74   	 */
75   	
76   	/** solution status after solving LP */
77   	enum SCIP_LinearConsType
78   	{
79   	   SCIP_LINEARCONSTYPE_INVALIDCONS = -1,     /**< this is no valid linear constraint type */
80   	   SCIP_LINEARCONSTYPE_LINEAR      =  0,     /**< this is the common linear constraint */
81   	   SCIP_LINEARCONSTYPE_LOGICOR     =  1,     /**< this is a logicor constraint */
82   	   SCIP_LINEARCONSTYPE_KNAPSACK    =  2,     /**< this is a knapsack constraint */
83   	#ifndef WITHEQKNAPSACK
84   	   SCIP_LINEARCONSTYPE_SETPPC      =  3      /**< this is a setppc constraint */
85   	#else
86   	   SCIP_LINEARCONSTYPE_SETPPC      =  3,     /**< this is a setppc constraint */
87   	   SCIP_LINEARCONSTYPE_EQKNAPSACK  =  4      /**< this is a equality knapsack constraint */
88   	#endif
89   	};
90   	typedef enum SCIP_LinearConsType SCIP_LINEARCONSTYPE;
91   	
92   	/** creates and captures a pseudoboolean constraint, with given linear and and-constraints
93   	 *
94   	 *  @note intvar must currently be NULL
95   	 */
96   	SCIP_EXPORT
97   	SCIP_RETCODE SCIPcreateConsPseudobooleanWithConss(
98   	   SCIP*                 scip,               /**< SCIP data structure */
99   	   SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
100  	   const char*           name,               /**< name of constraint */
101  	   SCIP_CONS*            lincons,            /**< associated linear constraint */
102  	   SCIP_LINEARCONSTYPE   linconstype,        /**< linear constraint type of associated linear constraint */
103  	   SCIP_CONS**           andconss,           /**< associated and-constraints */
104  	   SCIP_Real*            andcoefs,           /**< associated coefficients of and-constraints */
105  	   int                   nandconss,          /**< number of associated and-constraints */
106  	   SCIP_VAR*             indvar,             /**< indicator variable if it's a soft constraint, or NULL */
107  	   SCIP_Real             weight,             /**< weight of the soft constraint, if it is one */
108  	   SCIP_Bool             issoftcons,         /**< is this a soft constraint */
109  	   SCIP_VAR*             intvar,             /**< an artificial variable which was added only for the objective function,
110  	                                              *   if this variable is not NULL this constraint (without this integer
111  	                                              *   variable) describes the objective function */
112  	   SCIP_Real             lhs,                /**< left hand side of constraint */
113  	   SCIP_Real             rhs,                /**< right hand side of constraint */
114  	   SCIP_Bool             initial,            /**< should the LP relaxation of constraint be in the initial LP?
115  	                                              *   Usually set to TRUE. Set to FALSE for 'lazy constraints'. */
116  	   SCIP_Bool             separate,           /**< should the constraint be separated during LP processing?
117  	                                              *   Usually set to TRUE. */
118  	   SCIP_Bool             enforce,            /**< should the constraint be enforced during node processing?
119  	                                              *   TRUE for model constraints, FALSE for additional, redundant
120  	                                              *   constraints. */
121  	   SCIP_Bool             check,              /**< should the constraint be checked for feasibility?
122  	                                              *   TRUE for model constraints, FALSE for additional, redundant
123  	                                              *   constraints. */
124  	   SCIP_Bool             propagate,          /**< should the constraint be propagated during node processing?
125  	                                              *   Usually set to TRUE. */
126  	   SCIP_Bool             local,              /**< is constraint only valid locally?
127  	                                              *   Usually set to FALSE. Has to be set to TRUE, e.g., for branching
128  	                                              *   constraints. */
129  	   SCIP_Bool             modifiable,         /**< is constraint modifiable (subject to column generation)?
130  	                                              *   Usually set to FALSE. In column generation applications, set to TRUE if
131  	                                              *   pricing adds coefficients to this constraint. */
132  	   SCIP_Bool             dynamic,            /**< is constraint subject to aging?
133  	                                              *   Usually set to FALSE. Set to TRUE for own cuts which are seperated as
134  	                                              *   constraints. */
135  	   SCIP_Bool             removable,          /**< should the relaxation be removed from the LP due to aging or cleanup?
136  	                                              *   Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user
137  	                                              *   cuts'. */
138  	   SCIP_Bool             stickingatnode      /**< should the constraint always be kept at the node where it was added, even
139  	                                              *   if it may be moved to a more global node?
140  	                                              *   Usually set to FALSE. Set to TRUE to for constraints that represent
141  	                                              *   node data. */
142  	   );
143  	
144  	/** creates and captures a pseudoboolean constraint
145  	 *
146  	 *  @note linear and nonlinear terms can be added using SCIPaddCoefPseudoboolean() and SCIPaddTermPseudoboolean(),
147  	 *        respectively
148  	 *
149  	 *  @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
150  	 *
151  	 *  @note intvar must currently be NULL
152  	 */
153  	SCIP_EXPORT
154  	SCIP_RETCODE SCIPcreateConsPseudoboolean(
155  	   SCIP*                 scip,               /**< SCIP data structure */
156  	   SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
157  	   const char*           name,               /**< name of constraint */
158  	   SCIP_VAR**            linvars,            /**< variables of the linear part, or NULL */
159  	   int                   nlinvars,           /**< number of variables of the linear part */
160  	   SCIP_Real*            linvals,            /**< coefficients of linear part, or NULL */
161  	   SCIP_VAR***           terms,              /**< nonlinear terms of variables, or NULL */
162  	   int                   nterms,             /**< number of terms of variables of nonlinear term */
163  	   int*                  ntermvars,          /**< number of variables in nonlinear terms, or NULL */
164  	   SCIP_Real*            termvals,           /**< coefficients of nonlinear parts, or NULL */
165  	   SCIP_VAR*             indvar,             /**< indicator variable if it's a soft constraint, or NULL */
166  	   SCIP_Real             weight,             /**< weight of the soft constraint, if it is one */
167  	   SCIP_Bool             issoftcons,         /**< is this a soft constraint */
168  	   SCIP_VAR*             intvar,             /**< an artificial variable which was added only for the objective function,
169  	                                              *   if this variable is not NULL this constraint (without this integer
170  	                                              *   variable) describes the objective function */
171  	   SCIP_Real             lhs,                /**< left hand side of constraint */
172  	   SCIP_Real             rhs,                /**< right hand side of constraint */
173  	   SCIP_Bool             initial,            /**< should the LP relaxation of constraint be in the initial LP?
174  	                                              *   Usually set to TRUE. Set to FALSE for 'lazy constraints'. */
175  	   SCIP_Bool             separate,           /**< should the constraint be separated during LP processing?
176  	                                              *   Usually set to TRUE. */
177  	   SCIP_Bool             enforce,            /**< should the constraint be enforced during node processing?
178  	                                              *   TRUE for model constraints, FALSE for additional, redundant constraints. */
179  	   SCIP_Bool             check,              /**< should the constraint be checked for feasibility?
180  	                                              *   TRUE for model constraints, FALSE for additional, redundant constraints. */
181  	   SCIP_Bool             propagate,          /**< should the constraint be propagated during node processing?
182  	                                              *   Usually set to TRUE. */
183  	   SCIP_Bool             local,              /**< is constraint only valid locally?
184  	                                              *   Usually set to FALSE. Has to be set to TRUE, e.g., for branching constraints. */
185  	   SCIP_Bool             modifiable,         /**< is constraint modifiable (subject to column generation)?
186  	                                              *   Usually set to FALSE. In column generation applications, set to TRUE if pricing
187  	                                              *   adds coefficients to this constraint. */
188  	   SCIP_Bool             dynamic,            /**< is constraint subject to aging?
189  	                                              *   Usually set to FALSE. Set to TRUE for own cuts which
190  	                                              *   are separated as constraints. */
191  	   SCIP_Bool             removable,          /**< should the relaxation be removed from the LP due to aging or cleanup?
192  	                                              *   Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'. */
193  	   SCIP_Bool             stickingatnode      /**< should the constraint always be kept at the node where it was added, even
194  	                                              *   if it may be moved to a more global node?
195  	                                              *   Usually set to FALSE. Set to TRUE to for constraints that represent node data. */
196  	   );
197  	
198  	/** creates and captures a pseudoboolean constraint
199  	 *  in its most basic variant, i. e., with all constraint flags set to their default values, which can be set
200  	 *  afterwards using SCIPsetConsFLAGNAME() in scip.h
201  	 *
202  	 *  @see SCIPcreateConsPseudoboolean() for the default constraint flag configuration
203  	 *
204  	 *  @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
205  	 *
206  	 *  @note intvar must currently be NULL
207  	 */
208  	SCIP_EXPORT
209  	SCIP_RETCODE SCIPcreateConsBasicPseudoboolean(
210  	   SCIP*                 scip,               /**< SCIP data structure */
211  	   SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
212  	   const char*           name,               /**< name of constraint */
213  	   SCIP_VAR**            linvars,            /**< variables of the linear part, or NULL */
214  	   int                   nlinvars,           /**< number of variables of the linear part */
215  	   SCIP_Real*            linvals,            /**< coefficients of linear part, or NULL */
216  	   SCIP_VAR***           terms,              /**< nonlinear terms of variables, or NULL */
217  	   int                   nterms,             /**< number of terms of variables of nonlinear term */
218  	   int*                  ntermvars,          /**< number of variables in nonlinear terms, or NULL */
219  	   SCIP_Real*            termvals,           /**< coefficients of nonlinear parts, or NULL */
220  	   SCIP_VAR*             indvar,             /**< indicator variable if it's a soft constraint, or NULL */
221  	   SCIP_Real             weight,             /**< weight of the soft constraint, if it is one */
222  	   SCIP_Bool             issoftcons,         /**< is this a soft constraint */
223  	   SCIP_VAR*             intvar,             /**< a artificial variable which was added only for the objective function,
224  	                                              *   if this variable is not NULL this constraint (without this integer
225  	                                              *   variable) describes the objective function */
226  	   SCIP_Real             lhs,                /**< left hand side of constraint */
227  	   SCIP_Real             rhs                 /**< right hand side of constraint */
228  	   );
229  	
230  	/** adds linear term pseudo boolean constraint (if it is not zero)
231  	 *
232  	 * @note you can only add a coefficient if the special type of linear constraint won't changed
233  	 *
234  	 * @todo if adding a coefficient would change the type of the special linear constraint, we need to erase it and
235  	 *       create a new linear constraint
236  	 */
237  	SCIP_EXPORT
238  	SCIP_RETCODE SCIPaddCoefPseudoboolean(
239  	   SCIP*const            scip,               /**< SCIP data structure */
240  	   SCIP_CONS*const       cons,               /**< pseudoboolean constraint */
241  	   SCIP_VAR* const       var,                /**< variable of constraint entry */
242  	   SCIP_Real const       val                 /**< coefficient of constraint entry */
243  	   );
244  	
245  	/** adds nonlinear term to pseudo boolean constraint (if it is not zero)
246  	 *
247  	 * @note you can only add a coefficient if the special type of linear constraint won't changed
248  	 *
249  	 * @todo if adding a coefficient would change the type of the special linear constraint, we need to erase it and
250  	 *       create a new linear constraint
251  	 */
252  	SCIP_EXPORT
253  	SCIP_RETCODE SCIPaddTermPseudoboolean(
254  	   SCIP*const            scip,               /**< SCIP data structure */
255  	   SCIP_CONS*const       cons,               /**< pseudoboolean constraint */
256  	   SCIP_VAR**const       vars,               /**< variables of the nonlinear term */
257  	   int const             nvars,              /**< number of variables of the nonlinear term */
258  	   SCIP_Real const       val                 /**< coefficient of constraint entry */
259  	   );
260  	
261  	/** gets indicator variable of pseudoboolean constraint, or NULL if there is no */
262  	SCIP_EXPORT
263  	SCIP_VAR* SCIPgetIndVarPseudoboolean(
264  	   SCIP*const            scip,               /**< SCIP data structure */
265  	   SCIP_CONS*const       cons                /**< pseudoboolean constraint */
266  	   );
267  	
268  	/** gets linear constraint of pseudoboolean constraint */
269  	SCIP_EXPORT
270  	SCIP_CONS* SCIPgetLinearConsPseudoboolean(
271  	   SCIP*const            scip,               /**< SCIP data structure */
272  	   SCIP_CONS*const       cons                /**< pseudoboolean constraint */
273  	   );
274  	
275  	/** gets type of linear constraint of pseudoboolean constraint */
276  	SCIP_EXPORT
277  	SCIP_LINEARCONSTYPE SCIPgetLinearConsTypePseudoboolean(
278  	   SCIP*const            scip,               /**< SCIP data structure */
279  	   SCIP_CONS*const       cons                /**< pseudoboolean constraint */
280  	   );
281  	
282  	/** gets number of linear variables without artificial terms variables of pseudoboolean constraint */
283  	SCIP_EXPORT
284  	int SCIPgetNLinVarsWithoutAndPseudoboolean(
285  	   SCIP*const            scip,               /**< SCIP data structure */
286  	   SCIP_CONS*const       cons                /**< pseudoboolean constraint */
287  	   );
288  	
289  	/** gets linear constraint of pseudoboolean constraint */
290  	SCIP_EXPORT
291  	SCIP_RETCODE SCIPgetLinDatasWithoutAndPseudoboolean(
292  	   SCIP*const            scip,               /**< SCIP data structure */
293  	   SCIP_CONS*const       cons,               /**< pseudoboolean constraint */
294  	   SCIP_VAR**const       linvars,            /**< array to store and-constraints */
295  	   SCIP_Real*const       lincoefs,           /**< array to store and-coefficients */
296  	   int*const             nlinvars            /**< pointer to store the required array size for and-constraints, have to
297  	                                              *   be initialized with size of given array */
298  	   );
299  	
300  	/** gets and-constraints of pseudoboolean constraint */
301  	SCIP_EXPORT
302  	SCIP_RETCODE SCIPgetAndDatasPseudoboolean(
303  	   SCIP*const            scip,               /**< SCIP data structure */
304  	   SCIP_CONS*const       cons,               /**< pseudoboolean constraint */
305  	   SCIP_CONS**const      andconss,           /**< array to store and-constraints */
306  	   SCIP_Real*const       andcoefs,           /**< array to store and-coefficients */
307  	   int*const             nandconss           /**< pointer to store the required array size for and-constraints, have to
308  	                                              *   be initialized with size of given array */
309  	   );
310  	
311  	/** gets number of and constraints of pseudoboolean constraint */
312  	SCIP_EXPORT
313  	int SCIPgetNAndsPseudoboolean(
314  	   SCIP*const            scip,               /**< SCIP data structure */
315  	   SCIP_CONS*const       cons                /**< pseudoboolean constraint */
316  	   );
317  	
318  	/** changes left hand side of pseudoboolean constraint
319  	 *
320  	 * @note you can only change the left hand side if the special type of linear constraint won't changed
321  	 *
322  	 * @todo if changing the left hand side would change the type of the special linear constraint, we need to erase it
323  	 *       and create a new linear constraint
324  	 */
325  	SCIP_EXPORT
326  	SCIP_RETCODE SCIPchgLhsPseudoboolean(
327  	   SCIP*const            scip,               /**< SCIP data structure */
328  	   SCIP_CONS*const       cons,               /**< pseudoboolean constraint */
329  	   SCIP_Real const       lhs                 /**< new left hand side */
330  	   );
331  	
332  	/** changes right hand side of pseudoboolean constraint
333  	 *
334  	 * @note you can only change the right hand side if the special type of linear constraint won't changed
335  	 *
336  	 * @todo if changing the right hand side would change the type of the special linear constraint, we need to erase it
337  	 *       and create a new linear constraint
338  	 */
339  	SCIP_EXPORT
340  	SCIP_RETCODE SCIPchgRhsPseudoboolean(
341  	   SCIP*const            scip,               /**< SCIP data structure */
342  	   SCIP_CONS*const       cons,               /**< pseudoboolean constraint */
343  	   SCIP_Real const       rhs                 /**< new right hand side */
344  	   );
345  	
346  	/** get left hand side of pseudoboolean constraint */
347  	SCIP_EXPORT
348  	SCIP_Real SCIPgetLhsPseudoboolean(
349  	   SCIP*const            scip,               /**< SCIP data structure */
350  	   SCIP_CONS*const       cons                /**< pseudoboolean constraint */
351  	   );
352  	
353  	/** get right hand side of pseudoboolean constraint */
354  	SCIP_EXPORT
355  	SCIP_Real SCIPgetRhsPseudoboolean(
356  	   SCIP*const            scip,               /**< SCIP data structure */
357  	   SCIP_CONS*const       cons                /**< pseudoboolean constraint */
358  	   );
359  	
360  	/** @} */
361  	
362  	/** @} */
363  	
364  	#ifdef __cplusplus
365  	}
366  	#endif
367  	
368  	#endif
369