1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2 /*                                                                           */
3 /*                  This file is part of the program and library             */
4 /*         SCIP --- Solving Constraint Integer Programs                      */
5 /*                                                                           */
6 /*    Copyright (C) 2002-2021 Konrad-Zuse-Zentrum                            */
7 /*                            fuer Informationstechnik Berlin                */
8 /*                                                                           */
9 /*  SCIP is distributed under the terms of the ZIB Academic License.         */
10 /*                                                                           */
11 /*  You should have received a copy of the ZIB Academic License              */
12 /*  along with SCIP; see the file COPYING. If not visit scipopt.org.         */
13 /*                                                                           */
14 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
15 
16 /**@file   presol_dualcomp.h
17  * @ingroup PRESOLVERS
18  * @brief  dual compensation presolver
19  * @author Dieter Weninger
20  *
21  * This presolver looks for variables with
22  *         i) objcoef >= 0 and exactly one downlock
23  *        ii) objcoef <= 0 and exactly one uplock
24  * and fixes the variable in case i) at the lower bound and in case ii) at the
25  * upper bound if a combination of singleton continuous variables can compensate
26  * the downlock in case i) and the uplock in case ii).
27  */
28 
29 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
30 
31 #ifndef __SCIP_PRESOL_DUALCOMP_H__
32 #define __SCIP_PRESOL_DUALCOMP_H__
33 
34 #include "scip/def.h"
35 #include "scip/type_retcode.h"
36 #include "scip/type_scip.h"
37 
38 #ifdef __cplusplus
39 extern "C" {
40 #endif
41 
42 /** creates the dualcomp presolver and includes it in SCIP
43  *
44  * @ingroup PresolverIncludes
45  */
46 SCIP_EXPORT
47 SCIP_RETCODE SCIPincludePresolDualcomp(
48    SCIP*                 scip                /**< SCIP data structure */
49    );
50 
51 #ifdef __cplusplus
52 }
53 #endif
54 
55 #endif
56