void clq_sep_separate( CliqueSeparation *sep, const double x[] )
{
const CGraph *cgraph = sep->cgraph;
clq_set_clear( sep->clqSet );
clq_set_clear( sep->clqSetOrig );
clq_sep_check_node_cap( sep );
CliqueSet *clqSetOrig = sep->clqSetOrig;
clq_set_clear( clqSetOrig ); /* before extension, orig indexes */
CliqueSet *clqSet = sep->clqSet;
clq_set_clear( clqSet ); /* final clique set */
int *iv = sep->iv;
const double minFrac = sep->minFrac;
{
IntQueue queue;
int i, *neighs, csize = cgraph_size(cgraph);
char inQueue[csize]; //'1' if a vertices is already in queue - '0' otherwise
neighs = xmalloc(sizeof(int) * csize * 10);
vint_queue_init(&queue, csize);
for(i = 0; i < csize; i++)
{
if(cgraph_degree(cgraph, i) == 0) //deleting variables that are not binary
{
iv[i] = -1;
inQueue[i] = '0'; //just to avoid memory problems
}
else if(cgraph_degree(cgraph, i) == 1 || fracPart(x[i]) < minFrac)
{ //integer variables and variables that have conflict only with their complements are deleted
iv[i] = -1;
vint_queue_push(&queue, i);
inQueue[i] = '1';
}
else
{
iv[i] = cgraph_degree(cgraph, i);
inQueue[i] = '0';
}
}
while(!vint_queue_is_empty(&queue))
{
int v;
vint_queue_pop(&queue, &v);
int nsize = cgraph_get_all_conflicting(cgraph, v, neighs, csize * 10);
for(i = 0; i < nsize; i++)
{
int u = neighs[i];
if(iv[u] == -1) continue;
assert(iv[u] > 0);
iv[u]--; //considering v was deleted
if(iv[u] == 0)
{
iv[u] = -1;
if(inQueue[u] == '0')
{
vint_queue_push(&queue, u);
inQueue[u] = '1';
}
}
}
}
int idx = 0;
for(i = 0; i < csize; i++)
if(iv[i] > 0)
iv[i] = idx++;
free(neighs);
vint_queue_clean(&queue);
}
CGraph *ppcg = cgraph_create_induced_subgraph( cgraph, iv );
cgraph_set_low_degree( ppcg, sep->enumUsage );
clq_sep_update_ppgraph_weights( ppcg, cgraph_size(cgraph), x );
/* if enumeration is used, iv will be update*/
if (sep->verbose)
cgraph_print_summary( ppcg, "pre-processed graph - part 1" );
/* separation works with integer weights */
const int minW = (int)(1000.0 + (sep->minViol*1000.0));
char enumerationComplete = 0;
if ( sep->enumUsage > 0 )
{
clq_enum_set_min_weight( sep->clqEnum, minW );
int enumNodes = clq_sep_enum_all_cliques_low_degree_nodes( sep, iv, ppcg );
if (enumNodes < cgraph_size(ppcg))
{
/* more processing will be needed, creating a another preprocesses graph
without already enumerated nodes */
cgraph_free( &ppcg );
ppcg = cgraph_create_induced_subgraph( cgraph, iv );
cgraph_set_low_degree( ppcg, sep->enumUsage );
clq_sep_update_ppgraph_weights( ppcg, cgraph_size(cgraph), x );
if (sep->verbose)
cgraph_print_summary( ppcg, "pre-processed graph - part 2" );
}
else
{
if (sep->verbose)
printf("pre-processed graph - part 2 - no nodes left. all cliques have been enumerated.\n");
enumerationComplete = 1;
}
}
int firstGraspClique = clq_set_number_of_cliques( clqSetOrig );
if ( (!enumerationComplete) && (cgraph_size(ppcg)>=2) )
{
sep->bk = bk_create( ppcg );
clock_t startBK = clock();
int stillWorkToDo = bk_run( sep->bk, minW, sep->maxTimeBK );
clock_t endBK = clock();
if (sep->verbose)
{
printf("bk took %.3g seconds\n", ((double)endBK-startBK)/((double)CLOCKS_PER_SEC) );
}
CliqueSet *bkClqSet = bk_get_clq_set(sep->bk);
if (bkClqSet)
{
if (clq_set_number_of_cliques( bkClqSet ))
{
#ifdef DEBUG
int nc = clq_set_number_of_cliques( bkClqSet );
int ic;
for ( ic = 0 ; (ic<nc) ; ++ic )
{
const IntSet *is = clq_set_get_clique( bkClqSet, ic );
int n1, n2;
if (!clq_validate( ppcg, vint_set_size(is), vint_set_get_elements(is), &n1, &n2 ))
{
fprintf( stderr, "Nodes %d and %d are not in conflict in ppcg.\n", n1, n2 );
exit( EXIT_FAILURE );
}
int j;
for ( j=0 ; (j<vint_set_size(is)) ; ++j )
{
const int vidx = vint_set_get_elements(is)[j];
assert( vidx >=0 );
assert( vidx < cgraph_size(ppcg) );
}
}
#endif
clq_set_add_using_original_indexes( clqSetOrig, bkClqSet , cgraph_get_original_node_indexes( ppcg ) );
}
}
if (stillWorkToDo)
{
Grasp *grasp = grasp_create( ppcg, minW );
if (sep->verbose)
{
printf("running grasp\n");
}
clock_t graspStart = clock();
grasp_run( grasp );
const CliqueSet *graspCliques = grasp_solution_set(grasp); /* before extension, pp indexes */
clq_set_add_using_original_indexes( clqSetOrig, graspCliques, cgraph_get_original_node_indexes( ppcg ) );
grasp_free( &grasp );
clock_t graspEnd = clock();
if (sep->verbose)
{
printf("grasp took %.3f seconds.\n", ((double)graspEnd-graspStart)/((double)CLOCKS_PER_SEC) );
}
}
bk_free( (sep->bk) );
sep->bk = NULL;
}
/* extending cliques */
vmg_adjust_vector_capacity( (void**)&(sep->extended), &(sep->extendedCap), clq_set_number_of_cliques(clqSetOrig), sizeof(char) );
char *extended = sep->extended;
memset( extended, 0, sizeof(char)*clq_set_number_of_cliques( clqSetOrig ) );
/* since grasp ran in a restricted subgraph, cliques found may be dominated by the ones
found in the enumeration phase, checking ... */
{
int i;
for ( i=firstGraspClique ; (i<clq_set_number_of_cliques(clqSetOrig)) ; ++i )
{
const IntSet *graspClique = clq_set_get_clique( clqSetOrig, i );
int j;
for ( j=0 ; (j<firstGraspClique) ; ++j )
if ( clq_dominates( clq_set_get_clique( clqSetOrig, j ), graspClique ) )
extended[i] = 1;
}
}
if (sep->extendCliques)
{
clock_t startExtend = clock();
CliqueExtender *clqe = sep->clqe;
CliqueExtendingMethod clqem = CLQEM_RANDOM;
if (sep->hasCosts)
{
clqe_set_costs( clqe, sep->costs, cgraph_size(cgraph) );
clqem = CLQEM_PRIORITY_GREEDY;
}
int i;
for ( i=0 ; (i<clq_set_number_of_cliques( clqSetOrig )) ; ++i )
if (!extended[i])
extended[i] = clqe_extend( clqe, cgraph, clq_set_get_clique(clqSetOrig,i), clq_set_weight(clqSetOrig,i), clqem );
/* adding all extended cliques */
clq_set_add_cliques( clqSet, clqe_get_cliques( clqe ) );
clock_t endExtend = clock();
const double timeExtend = ((double)endExtend-startExtend) / ((double)CLOCKS_PER_SEC);
if (sep->verbose)
{
printf("clique extension took %.3f seconds.\n", timeExtend);
}
}
/* adding cliques which were not extended */
{
int i;
for ( i=0 ; (i<clq_set_number_of_cliques(clqSetOrig)) ; ++i )
if ( !extended[i] )
clq_set_add( clqSet, clq_set_clique_size(clqSetOrig,i), clq_set_clique_elements(clqSetOrig,i), clq_set_weight(clqSetOrig,i) );
}
/* need to be informed again next call */
sep->hasCosts = 0;
cgraph_free( &ppcg );
}
void clq_sep_separate( CliqueSeparation *sep, const double x[] )
{
const CGraph *cgraph = sep->cgraph;
clq_set_clear( sep->clqSet );
clq_set_clear( sep->clqSetOrig );
clq_sep_check_node_cap( sep );
CliqueSet *clqSetOrig = sep->clqSetOrig;
clq_set_clear( clqSetOrig ); /* before extension, orig indexes */
CliqueSet *clqSet = sep->clqSet;
clq_set_clear( clqSet ); /* final clique set */
int *iv = sep->iv;
const double minFrac = sep->minFrac;
{
IntQueue queue;
int i, *neighs, csize = cgraph_size(cgraph);
char inQueue[csize]; //'1' if a vertices is already in queue - '0' otherwise
neighs = xmalloc(sizeof(int) * csize * 10);
vint_queue_init(&queue, csize);
for(i = 0; i < csize; i++)
{
if(cgraph_degree(cgraph, i) == 0) //deleting variables that are not binary
{
iv[i] = -1;
inQueue[i] = '0'; //just to avoid memory problems
}
else if(cgraph_degree(cgraph, i) == 1 || (fracPart(x[i]) < minFrac && x[i] < 0.99))
{ //integer variables and variables that have conflict only with their complements are deleted
iv[i] = -1;
vint_queue_push(&queue, i);
inQueue[i] = '1';
}
else
{
iv[i] = cgraph_degree(cgraph, i);
inQueue[i] = '0';
}
}
while(!vint_queue_is_empty(&queue))
{
int v;
vint_queue_pop(&queue, &v);
int nsize = cgraph_get_all_conflicting(cgraph, v, neighs, csize * 10);
for(i = 0; i < nsize; i++)
{
int u = neighs[i];
if(iv[u] == -1) continue;
assert(iv[u] > 0);
iv[u]--; //considering v was deleted
if(iv[u] == 0)
{
iv[u] = -1;
if(inQueue[u] == '0')
{
vint_queue_push(&queue, u);
inQueue[u] = '1';
}
}
}
}
int idx = 0;
for(i = 0; i < csize; i++)
if(iv[i] > 0)
iv[i] = idx++;
free(neighs);
vint_queue_clean(&queue);
}
CGraph *ppcg = cgraph_create_induced_subgraph( cgraph, iv );
clq_sep_update_ppgraph_weights( ppcg, cgraph_size(cgraph), x );
if (sep->verbose)
cgraph_print_summary( ppcg, "pre-processed graph - part 1" );
/* separation works with integer weights */
const int minW = (int)(1000.0 + (sep->minViol*1000.0));
if(cgraph_size(ppcg)>=2)
{
sep->bk = bk_create( ppcg );
clock_t startBK = clock();
bk_set_max_it(sep->bk, sep->maxItBK);
bk_set_min_weight(sep->bk, minW);
bk_run( sep->bk );
clock_t endBK = clock();
if (sep->verbose)
{
printf("bk took %.3g seconds\n", ((double)endBK-startBK)/((double)CLOCKS_PER_SEC) );
}
const CliqueSet *bkClqSet = bk_get_clq_set(sep->bk);
if (bkClqSet)
{
if (clq_set_number_of_cliques( bkClqSet ))
{
#ifdef DEBUG
int nc = clq_set_number_of_cliques( bkClqSet );
int ic;
for ( ic = 0 ; (ic<nc) ; ++ic )
{
const IntSet *is = clq_set_get_clique( bkClqSet, ic );
int n1, n2;
if (!clq_validate( ppcg, vint_set_size(is), vint_set_get_elements(is), &n1, &n2 ))
{
fprintf( stderr, "Nodes %d and %d are not in conflict in ppcg.\n", n1, n2 );
exit( EXIT_FAILURE );
}
int j;
for ( j=0 ; (j<vint_set_size(is)) ; ++j )
{
const int vidx = vint_set_get_elements(is)[j];
assert( vidx >=0 );
assert( vidx < cgraph_size(ppcg) );
}
}
#endif
clq_set_add_using_original_indexes( clqSetOrig, bkClqSet , cgraph_get_original_node_indexes( ppcg ) );
}
}
bk_free( (sep->bk) );
sep->bk = NULL;
}
/* extending cliques */
vmg_adjust_vector_capacity( (void**)&(sep->extended), &(sep->extendedCap), clq_set_number_of_cliques(clqSetOrig), sizeof(char) );
char *extended = sep->extended;
memset( extended, 0, sizeof(char)*clq_set_number_of_cliques( clqSetOrig ) );
if (sep->extendCliques)
{
clock_t startExtend = clock();
CliqueExtender *clqe = sep->clqe;
if(sep->hasCosts)
clqe_set_costs( clqe, sep->costs, cgraph_size(cgraph) );
int i;
for ( i=0 ; (i<clq_set_number_of_cliques( clqSetOrig )) ; ++i )
extended[i] = clqe_extend( clqe, cgraph, clq_set_get_clique(clqSetOrig,i), clq_set_weight(clqSetOrig,i), sep->extendCliques );
/* adding all extended cliques */
clq_set_add_cliques( clqSet, clqe_get_cliques( clqe ) );
clock_t endExtend = clock();
const double timeExtend = ((double)endExtend-startExtend) / ((double)CLOCKS_PER_SEC);
if (sep->verbose)
{
printf("clique extension took %.3f seconds.\n", timeExtend);
}
}
/* adding cliques which were not extended */
{
int i;
for ( i=0 ; (i<clq_set_number_of_cliques(clqSetOrig)) ; ++i )
if ( !extended[i] )
clq_set_add( clqSet, clq_set_clique_size(clqSetOrig,i), clq_set_clique_elements(clqSetOrig,i), clq_set_weight(clqSetOrig,i) );
}
/* need to be informed again next call */
sep->hasCosts = 0;
cgraph_free( &ppcg );
}