diff options
Diffstat (limited to 'test/monniaux/glpk-4.65/src/api/minisat1.c')
| -rw-r--r-- | test/monniaux/glpk-4.65/src/api/minisat1.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/test/monniaux/glpk-4.65/src/api/minisat1.c b/test/monniaux/glpk-4.65/src/api/minisat1.c new file mode 100644 index 00000000..a669c487 --- /dev/null +++ b/test/monniaux/glpk-4.65/src/api/minisat1.c @@ -0,0 +1,161 @@ +/* minisat1.c (driver to MiniSat solver) */ + +/*********************************************************************** +* This code is part of GLPK (GNU Linear Programming Kit). +* +* Copyright (C) 2011-2016 Andrew Makhorin, Department for Applied +* Informatics, Moscow Aviation Institute, Moscow, Russia. All rights +* reserved. E-mail: <mao@gnu.org>. +* +* GLPK is free software: you can redistribute it and/or modify it +* under the terms of the GNU General Public License as published by +* the Free Software Foundation, either version 3 of the License, or +* (at your option) any later version. +* +* GLPK is distributed in the hope that it will be useful, but WITHOUT +* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY +* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public +* License for more details. +* +* You should have received a copy of the GNU General Public License +* along with GLPK. If not, see <http://www.gnu.org/licenses/>. +***********************************************************************/ + +#include "env.h" +#include "minisat.h" +#include "prob.h" + +int glp_minisat1(glp_prob *P) +{ /* solve CNF-SAT problem with MiniSat solver */ + solver *s; + GLPAIJ *aij; + int i, j, len, ret, *ind; + double sum; +#if 0 /* 04/IV-2016 */ + /* check problem object */ + if (P == NULL || P->magic != GLP_PROB_MAGIC) + xerror("glp_minisat1: P = %p; invalid problem object\n", + P); +#endif + if (P->tree != NULL) + xerror("glp_minisat1: operation not allowed\n"); + /* integer solution is currently undefined */ + P->mip_stat = GLP_UNDEF; + P->mip_obj = 0.0; + /* check that problem object encodes CNF-SAT instance */ + if (glp_check_cnfsat(P) != 0) + { xprintf("glp_minisat1: problem object does not encode CNF-SAT " + "instance\n"); + ret = GLP_EDATA; + goto done; + } +#if 0 /* 08/I-2017 by cmatraki */ +#if 1 /* 07/XI-2015 */ + if (sizeof(void *) != sizeof(int)) + { xprintf("glp_minisat1: sorry, MiniSat solver is not supported " + "on 64-bit platforms\n"); + ret = GLP_EFAIL; + goto done; + } +#endif +#else + if (sizeof(void *) != sizeof(size_t)) + { xprintf("glp_minisat1: sorry, MiniSat solver is not supported " + "on this platform\n"); + ret = GLP_EFAIL; + goto done; + } +#endif + /* solve CNF-SAT problem */ + xprintf("Solving CNF-SAT problem...\n"); + xprintf("Instance has %d variable%s, %d clause%s, and %d literal%" + "s\n", P->n, P->n == 1 ? "" : "s", P->m, P->m == 1 ? "" : "s", + P->nnz, P->nnz == 1 ? "" : "s"); + /* if CNF-SAT has no clauses, it is satisfiable */ + if (P->m == 0) + { P->mip_stat = GLP_OPT; + for (j = 1; j <= P->n; j++) + P->col[j]->mipx = 0.0; + goto fini; + } + /* if CNF-SAT has an empty clause, it is unsatisfiable */ + for (i = 1; i <= P->m; i++) + { if (P->row[i]->ptr == NULL) + { P->mip_stat = GLP_NOFEAS; + goto fini; + } + } + /* prepare input data for the solver */ + s = solver_new(); + solver_setnvars(s, P->n); + ind = xcalloc(1+P->n, sizeof(int)); + for (i = 1; i <= P->m; i++) + { len = 0; + for (aij = P->row[i]->ptr; aij != NULL; aij = aij->r_next) + { ind[++len] = toLit(aij->col->j-1); + if (aij->val < 0.0) + ind[len] = lit_neg(ind[len]); + } + xassert(len > 0); +#if 0 /* 08/I-2017 by cmatraki */ + xassert(solver_addclause(s, &ind[1], &ind[1+len])); +#else + if (!solver_addclause(s, &ind[1], &ind[1+len])) + { /* found trivial conflict */ + xfree(ind); + solver_delete(s); + P->mip_stat = GLP_NOFEAS; + goto fini; + } +#endif + } + xfree(ind); + /* call the solver */ + s->verbosity = 1; + if (solver_solve(s, 0, 0)) + { /* instance is reported as satisfiable */ + P->mip_stat = GLP_OPT; + /* copy solution to the problem object */ + xassert(s->model.size == P->n); + for (j = 1; j <= P->n; j++) + { P->col[j]->mipx = + s->model.ptr[j-1] == l_True ? 1.0 : 0.0; + } + /* compute row values */ + for (i = 1; i <= P->m; i++) + { sum = 0; + for (aij = P->row[i]->ptr; aij != NULL; aij = aij->r_next) + sum += aij->val * aij->col->mipx; + P->row[i]->mipx = sum; + } + /* check integer feasibility */ + for (i = 1; i <= P->m; i++) + { if (P->row[i]->mipx < P->row[i]->lb) + { /* solution is wrong */ + P->mip_stat = GLP_UNDEF; + break; + } + } + } + else + { /* instance is reported as unsatisfiable */ + P->mip_stat = GLP_NOFEAS; + } + solver_delete(s); +fini: /* report the instance status */ + if (P->mip_stat == GLP_OPT) + { xprintf("SATISFIABLE\n"); + ret = 0; + } + else if (P->mip_stat == GLP_NOFEAS) + { xprintf("UNSATISFIABLE\n"); + ret = 0; + } + else + { xprintf("glp_minisat1: solver failed\n"); + ret = GLP_EFAIL; + } +done: return ret; +} + +/* eof */ |