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4    	/*         SCIP --- Solving Constraint Integer Programs                      */
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24   	
25   	/**@file   cons_xor.h
26   	 * @ingroup CONSHDLRS
27   	 * @brief  Constraint handler for XOR constraints,  \f$rhs = x_1 \oplus x_2 \oplus \dots  \oplus x_n\f$
28   	 * @author Tobias Achterberg
29   	 * @author Stefan Heinz
30   	 * @author Michael Winkler
31   	 *
32   	 */
33   	
34   	/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
35   	
36   	#ifndef __SCIP_CONS_XOR_H__
37   	#define __SCIP_CONS_XOR_H__
38   	
39   	
40   	#include "scip/def.h"
41   	#include "scip/type_cons.h"
42   	#include "scip/type_retcode.h"
43   	#include "scip/type_scip.h"
44   	#include "scip/type_var.h"
45   	
46   	#ifdef __cplusplus
47   	extern "C" {
48   	#endif
49   	
50   	/** creates the handler for xor constraints and includes it in SCIP
51   	 *
52   	 * @ingroup ConshdlrIncludes
53   	 * */
54   	SCIP_EXPORT
55   	SCIP_RETCODE SCIPincludeConshdlrXor(
56   	   SCIP*                 scip                /**< SCIP data structure */
57   	   );
58   	
59   	/**@addtogroup CONSHDLRS
60   	 *
61   	 * @{
62   	 *
63   	 * @name XOR Constraints
64   	 *
65   	 * @{
66   	 *
67   	 * This constraint handler deals with "xor" constraint. These are constraint of the form:
68   	 *
69   	 * \f[
70   	 *    rhs = x_1 \oplus x_2 \oplus \dots  \oplus x_n
71   	 * \f]
72   	 *
73   	 * where \f$x_i\f$ is a binary variable for all \f$i\f$ and \f$rhs\f$ is bool. The variables \f$x\f$'s are called
74   	 * operators. This constraint is satisfied if \f$rhs\f$ is TRUE and an odd number of the operators are TRUE or if the
75   	 * \f$rhs\f$ is FALSE and a even number of operators are TRUE. Hence, if the sum of \f$rhs\f$ and operators is even.
76   	 */
77   	
78   	/** creates and captures an xor constraint
79   	 *
80   	 *  @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
81   	 */
82   	SCIP_EXPORT
83   	SCIP_RETCODE SCIPcreateConsXor(
84   	   SCIP*                 scip,               /**< SCIP data structure */
85   	   SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
86   	   const char*           name,               /**< name of constraint */
87   	   SCIP_Bool             rhs,                /**< right hand side of the constraint */
88   	   int                   nvars,              /**< number of operator variables in the constraint */
89   	   SCIP_VAR**            vars,               /**< array with operator variables of constraint */
90   	   SCIP_Bool             initial,            /**< should the LP relaxation of constraint be in the initial LP?
91   	                                              *   Usually set to TRUE. Set to FALSE for 'lazy constraints'. */
92   	   SCIP_Bool             separate,           /**< should the constraint be separated during LP processing?
93   	                                              *   Usually set to TRUE. */
94   	   SCIP_Bool             enforce,            /**< should the constraint be enforced during node processing?
95   	                                              *   TRUE for model constraints, FALSE for additional, redundant constraints. */
96   	   SCIP_Bool             check,              /**< should the constraint be checked for feasibility?
97   	                                              *   TRUE for model constraints, FALSE for additional, redundant constraints. */
98   	   SCIP_Bool             propagate,          /**< should the constraint be propagated during node processing?
99   	                                              *   Usually set to TRUE. */
100  	   SCIP_Bool             local,              /**< is constraint only valid locally?
101  	                                              *   Usually set to FALSE. Has to be set to TRUE, e.g., for branching constraints. */
102  	   SCIP_Bool             modifiable,         /**< is constraint modifiable (subject to column generation)?
103  	                                              *   Usually set to FALSE. In column generation applications, set to TRUE if pricing
104  	                                              *   adds coefficients to this constraint. */
105  	   SCIP_Bool             dynamic,            /**< is constraint subject to aging?
106  	                                              *   Usually set to FALSE. Set to TRUE for own cuts which
107  	                                              *   are separated as constraints. */
108  	   SCIP_Bool             removable,          /**< should the relaxation be removed from the LP due to aging or cleanup?
109  	                                              *   Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'. */
110  	   SCIP_Bool             stickingatnode      /**< should the constraint always be kept at the node where it was added, even
111  	                                              *   if it may be moved to a more global node?
112  	                                              *   Usually set to FALSE. Set to TRUE to for constraints that represent node data. */
113  	   );
114  	
115  	/** creates and captures an xor constraint
116  	 *  in its most basic version, i. e., all constraint flags are set to their basic value as explained for the
117  	 *  method SCIPcreateConsXor(); all flags can be set via SCIPsetConsFLAGNAME-methods in scip.h
118  	 *
119  	 *  @see SCIPcreateConsXor() for information about the basic constraint flag configuration
120  	 *
121  	 *  @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
122  	 */
123  	SCIP_EXPORT
124  	SCIP_RETCODE SCIPcreateConsBasicXor(
125  	   SCIP*                 scip,               /**< SCIP data structure */
126  	   SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
127  	   const char*           name,               /**< name of constraint */
128  	   SCIP_Bool             rhs,                /**< right hand side of the constraint */
129  	   int                   nvars,              /**< number of operator variables in the constraint */
130  	   SCIP_VAR**            vars                /**< array with operator variables of constraint */
131  	   );
132  	
133  	/** gets number of variables in xor constraint */
134  	SCIP_EXPORT
135  	int SCIPgetNVarsXor(
136  	   SCIP*                 scip,               /**< SCIP data structure */
137  	   SCIP_CONS*            cons                /**< constraint data */
138  	   );
139  	
140  	/** gets array of variables in xor constraint */
141  	SCIP_EXPORT
142  	SCIP_VAR** SCIPgetVarsXor(
143  	   SCIP*                 scip,               /**< SCIP data structure */
144  	   SCIP_CONS*            cons                /**< constraint data */
145  	   );
146  	
147  	/** gets integer variable in xor constraint */
148  	SCIP_EXPORT
149  	SCIP_VAR* SCIPgetIntVarXor(
150  	   SCIP*                 scip,               /**< SCIP data structure */
151  	   SCIP_CONS*            cons                /**< constraint data */
152  	   );
153  	
154  	/** gets the right hand side of the xor constraint */
155  	SCIP_EXPORT
156  	SCIP_Bool SCIPgetRhsXor(
157  	   SCIP*                 scip,               /**< SCIP data structure */
158  	   SCIP_CONS*            cons                /**< constraint data */
159  	   );
160  	
161  	/** @} */
162  	
163  	/** @} */
164  	
165  	#ifdef __cplusplus
166  	}
167  	#endif
168  	
169  	#endif
170