6 #include "heuristical.h"
7 #include "html_dumper.h"
10 #include "pbqp_edge.h"
11 #include "pbqp_edge_t.h"
12 #include "pbqp_node.h"
13 #include "pbqp_node_t.h"
16 static pbqp_edge **edge_bucket;
17 static pbqp_node **node_buckets[4];
18 static pbqp_node **reduced_bucket = NULL;
19 static int buckets_filled = 0;
21 /* Forward declarations. */
22 static void apply_Brute_Force(pbqp *pbqp);
24 static void insert_into_edge_bucket(pbqp_edge *edge)
26 if (edge_bucket_contains(edge_bucket, edge)) {
27 /* Edge is already inserted. */
31 edge_bucket_insert(&edge_bucket, edge);
34 static void init_buckets(void)
38 edge_bucket_init(&edge_bucket);
39 node_bucket_init(&reduced_bucket);
41 for (i = 0; i < 4; ++i) {
42 node_bucket_init(&node_buckets[i]);
46 static void free_buckets(void)
50 for (i = 0; i < 4; ++i) {
51 node_bucket_free(&node_buckets[i]);
54 edge_bucket_free(&edge_bucket);
55 node_bucket_free(&reduced_bucket);
60 static void fill_node_buckets(pbqp *pbqp)
66 node_len = pbqp->num_nodes;
68 for (node_index = 0; node_index < node_len; ++node_index) {
70 pbqp_node *node = get_node(pbqp, node_index);
74 degree = pbqp_node_get_degree(node);
76 /* We have only one bucket for nodes with arity >= 3. */
81 node_bucket_insert(&node_buckets[degree], node);
87 static void normalize_towards_source(pbqp *pbqp, pbqp_edge *edge)
101 src_node = edge->src;
102 tgt_node = edge->tgt;
106 src_vec = src_node->costs;
107 tgt_vec = tgt_node->costs;
111 src_len = src_vec->len;
112 tgt_len = tgt_vec->len;
119 /* Normalize towards source node. */
120 for (src_index = 0; src_index < src_len; ++src_index) {
121 num min = pbqp_matrix_get_row_min(mat, src_index, tgt_vec);
124 if (src_vec->entries[src_index].data == INF_COSTS) {
125 pbqp_matrix_set_row_value(mat, src_index, 0);
127 pbqp_matrix_sub_row_value(mat, src_index, tgt_vec, min);
129 src_vec->entries[src_index].data = pbqp_add(
130 src_vec->entries[src_index].data, min);
132 if (min == INF_COSTS) {
134 unsigned edge_len = pbqp_node_get_degree(src_node);
136 for (edge_index = 0; edge_index < edge_len; ++edge_index) {
137 pbqp_edge *edge_candidate = src_node->edges[edge_index];
138 if (edge_candidate != edge) {
139 insert_into_edge_bucket(edge_candidate);
147 static void normalize_towards_target(pbqp *pbqp, pbqp_edge *edge)
161 src_node = edge->src;
162 tgt_node = edge->tgt;
166 src_vec = src_node->costs;
167 tgt_vec = tgt_node->costs;
171 src_len = src_vec->len;
172 tgt_len = tgt_vec->len;
179 for (tgt_index = 0; tgt_index < tgt_len; ++tgt_index) {
180 num min = pbqp_matrix_get_col_min(mat, tgt_index, src_vec);
183 if (tgt_vec->entries[tgt_index].data == INF_COSTS) {
184 pbqp_matrix_set_col_value(mat, tgt_index, 0);
186 pbqp_matrix_sub_col_value(mat, tgt_index, src_vec, min);
188 tgt_vec->entries[tgt_index].data = pbqp_add(
189 tgt_vec->entries[tgt_index].data, min);
191 if (min == INF_COSTS) {
193 unsigned edge_len = pbqp_node_get_degree(tgt_node);
195 for (edge_index = 0; edge_index < edge_len; ++edge_index) {
196 pbqp_edge *edge_candidate = tgt_node->edges[edge_index];
197 if (edge_candidate != edge) {
198 insert_into_edge_bucket(edge_candidate);
206 static void reorder_node(pbqp_node *node)
208 unsigned degree = pbqp_node_get_degree(node);
209 /* Assume node lost one incident edge. */
210 unsigned old_degree = degree + 1;
212 if (!buckets_filled) return;
214 /* Same bucket as before */
215 if (degree > 2) return;
217 if (!node_bucket_contains(node_buckets[old_degree], node)) {
218 /* Old arity is new arity, so we have nothing to do. */
219 assert(node_bucket_contains(node_buckets[degree], node));
223 /* Delete node from old bucket... */
224 node_bucket_remove(&node_buckets[old_degree], node);
226 /* ..and add to new one. */
227 node_bucket_insert(&node_buckets[degree], node);
230 static void check_melting_possibility(pbqp *pbqp, pbqp_edge *edge)
245 src_node = edge->src;
246 tgt_node = edge->tgt;
250 src_vec = src_node->costs;
251 tgt_vec = tgt_node->costs;
255 src_len = src_vec->len;
256 tgt_len = tgt_vec->len;
263 if (src_len == 1 && tgt_len == 1) {
264 //panic("Something is wrong");
268 for (src_index = 0; src_index < src_len; ++src_index) {
270 if (src_vec->entries[src_index].data == INF_COSTS) {
273 for (tgt_index = 0; tgt_index < tgt_len; ++tgt_index) {
274 if (tgt_vec->entries[tgt_index].data == INF_COSTS) {
277 if (mat->entries[src_index * tgt_len + tgt_index] == 0) {
286 if (mat->entries[src_index * tgt_len + tgt_index] == INF_COSTS) {
292 allRowsOk &= onlyOneZero;
296 for (tgt_index = 0; tgt_index < tgt_len; ++tgt_index) {
298 if (tgt_vec->entries[tgt_index].data == INF_COSTS) {
301 for (src_index = 0; src_index < src_len; ++src_index) {
302 if (src_vec->entries[src_index].data == INF_COSTS) {
305 if (mat->entries[src_index * tgt_len + tgt_index] == 0) {
314 if (mat->entries[src_index * tgt_len + tgt_index] == INF_COSTS) {
320 allColsOk &= onlyOneZero;
323 if (allRowsOk && allColsOk) {
328 static void simplify_edge(pbqp *pbqp, pbqp_edge *edge)
341 src_node = edge->src;
342 tgt_node = edge->tgt;
346 /* If edge are already deleted, we have nothing to do. */
347 if (!is_connected(src_node, edge) || !is_connected(tgt_node, edge))
350 if (pbqp->dump_file) {
352 sprintf(txt, "Simplification of Edge n%d-n%d", src_node->index, tgt_node->index);
353 dump_section(pbqp->dump_file, 3, txt);
356 src_vec = src_node->costs;
357 tgt_vec = tgt_node->costs;
361 src_len = src_vec->len;
362 tgt_len = tgt_vec->len;
369 if (pbqp->dump_file) {
370 fputs("Input:<br>\n", pbqp->dump_file);
371 dump_simplifyedge(pbqp, edge);
374 normalize_towards_source(pbqp, edge);
375 normalize_towards_target(pbqp, edge);
377 if (pbqp->dump_file) {
378 fputs("<br>\nOutput:<br>\n", pbqp->dump_file);
379 dump_simplifyedge(pbqp, edge);
382 if (pbqp_matrix_is_zero(mat, src_vec, tgt_vec)) {
383 if (pbqp->dump_file) {
384 fputs("edge has been eliminated<br>\n", pbqp->dump_file);
388 reorder_node(src_node);
389 reorder_node(tgt_node);
391 //check_melting_possibility(pbqp, edge);
395 static void initial_simplify_edges(pbqp *pbqp)
402 if (pbqp->dump_file) {
403 pbqp_dump_input(pbqp);
404 dump_section(pbqp->dump_file, 1, "2. Simplification of Cost Matrices");
407 node_len = pbqp->num_nodes;
411 /* First simplify all edges. */
412 for (node_index = 0; node_index < node_len; ++node_index) {
414 pbqp_node *node = get_node(pbqp, node_index);
421 edge_len = pbqp_node_get_degree(node);
423 for (edge_index = 0; edge_index < edge_len; ++edge_index) {
424 pbqp_edge *edge = edges[edge_index];
426 /* Simplify only once per edge. */
427 if (node != edge->src) continue;
429 simplify_edge(pbqp, edge);
434 num determine_solution(FILE *file)
441 dump_section(file, 1, "4. Determine Solution/Minimum");
442 dump_section(file, 2, "4.1. Trivial Solution");
445 /* Solve trivial nodes and calculate solution. */
446 node_len = node_bucket_get_length(node_buckets[0]);
447 for (node_index = 0; node_index < node_len; ++node_index) {
448 pbqp_node *node = node_buckets[0][node_index];
451 node->solution = vector_get_min_index(node->costs);
452 solution = pbqp_add(solution,
453 node->costs->entries[node->solution].data);
455 fprintf(file, "node n%d is set to %d<br>\n", node->index, node->solution);
456 dump_node(file, node);
461 dump_section(file, 2, "Minimum");
462 fprintf(file, "Minimum is equal to %lld.", solution);
468 static void back_propagate(pbqp *pbqp)
471 unsigned node_len = node_bucket_get_length(reduced_bucket);
474 if (pbqp->dump_file) {
475 dump_section(pbqp->dump_file, 2, "Back Propagation");
478 for (node_index = node_len; node_index > 0; --node_index) {
479 pbqp_node *node = reduced_bucket[node_index - 1];
481 switch (pbqp_node_get_degree(node)) {
483 back_propagate_RI(pbqp, node);
486 back_propagate_RII(pbqp, node);
489 panic("Only nodes with degree one or two should be in this bucket");
495 static void apply_heuristic_reductions(pbqp *pbqp)
498 if (edge_bucket_get_length(edge_bucket) > 0) {
500 } else if (node_bucket_get_length(node_buckets[1]) > 0) {
502 } else if (node_bucket_get_length(node_buckets[2]) > 0) {
504 } else if (node_bucket_get_length(node_buckets[3]) > 0) {
512 void solve_pbqp_heuristical(pbqp *pbqp)
514 /* Reduce nodes degree ... */
515 initial_simplify_edges(pbqp);
517 /* ... and put node into bucket representing their degree. */
518 fill_node_buckets(pbqp);
520 apply_heuristic_reductions(pbqp);
522 pbqp->solution = determine_solution(pbqp->dump_file);
524 //printf("solution: %lld\n", pbqp->solution);
526 /* Solve reduced nodes. */
527 back_propagate(pbqp);
532 void apply_edge(pbqp *pbqp)
534 pbqp_edge *edge = edge_bucket_pop(&edge_bucket);
536 simplify_edge(pbqp, edge);
539 void apply_RI(pbqp *pbqp)
541 pbqp_node *node = node_bucket_pop(&node_buckets[1]);
542 pbqp_edge *edge = node->edges[0];
543 pbqp_matrix *mat = edge->costs;
544 int is_src = edge->src == node;
545 pbqp_node *other_node;
547 assert(pbqp_node_get_degree(node) == 1);
550 other_node = edge->tgt;
552 other_node = edge->src;
555 if (pbqp->dump_file) {
557 sprintf(txt, "RI-Reduction of Node n%d", node->index);
558 dump_section(pbqp->dump_file, 2, txt);
559 pbqp_dump_graph(pbqp);
560 fputs("<br>\nBefore reduction:<br>\n", pbqp->dump_file);
561 dump_node(pbqp->dump_file, node);
562 dump_node(pbqp->dump_file, other_node);
563 dump_edge(pbqp->dump_file, edge);
567 pbqp_matrix_add_to_all_cols(mat, node->costs);
568 normalize_towards_target(pbqp, edge);
570 pbqp_matrix_add_to_all_rows(mat, node->costs);
571 normalize_towards_source(pbqp, edge);
573 disconnect_edge(other_node, edge);
575 if (pbqp->dump_file) {
576 fputs("<br>\nAfter reduction:<br>\n", pbqp->dump_file);
577 dump_node(pbqp->dump_file, other_node);
580 reorder_node(other_node);
582 /* Add node to back propagation list. */
583 node_bucket_insert(&reduced_bucket, node);
586 void apply_RII(pbqp *pbqp)
588 pbqp_node *node = node_bucket_pop(&node_buckets[2]);
589 pbqp_edge *src_edge = node->edges[0];
590 pbqp_edge *tgt_edge = node->edges[1];
591 int src_is_src = src_edge->src == node;
592 int tgt_is_src = tgt_edge->src == node;
593 pbqp_matrix *src_mat;
594 pbqp_matrix *tgt_mat;
609 assert(pbqp_node_get_degree(node) == 2);
612 src_node = src_edge->tgt;
614 src_node = src_edge->src;
618 tgt_node = tgt_edge->tgt;
620 tgt_node = tgt_edge->src;
623 /* Swap nodes if necessary. */
624 if (tgt_node->index < src_node->index) {
636 src_is_src = src_edge->src == node;
637 tgt_is_src = tgt_edge->src == node;
640 if (pbqp->dump_file) {
642 sprintf(txt, "RII-Reduction of Node n%d", node->index);
643 dump_section(pbqp->dump_file, 2, txt);
644 pbqp_dump_graph(pbqp);
645 fputs("<br>\nBefore reduction:<br>\n", pbqp->dump_file);
646 dump_node(pbqp->dump_file, src_node);
647 dump_edge(pbqp->dump_file, src_edge);
648 dump_node(pbqp->dump_file, node);
649 dump_edge(pbqp->dump_file, tgt_edge);
650 dump_node(pbqp->dump_file, tgt_node);
653 src_mat = src_edge->costs;
654 tgt_mat = tgt_edge->costs;
656 src_vec = src_node->costs;
657 tgt_vec = tgt_node->costs;
658 node_vec = node->costs;
660 row_len = src_vec->len;
661 col_len = tgt_vec->len;
662 node_len = node_vec->len;
664 mat = pbqp_matrix_alloc(pbqp, row_len, col_len);
666 for (row_index = 0; row_index < row_len; ++row_index) {
667 for (col_index = 0; col_index < col_len; ++col_index) {
668 vec = vector_copy(pbqp, node_vec);
671 vector_add_matrix_col(vec, src_mat, row_index);
673 vector_add_matrix_row(vec, src_mat, row_index);
677 vector_add_matrix_col(vec, tgt_mat, col_index);
679 vector_add_matrix_row(vec, tgt_mat, col_index);
682 mat->entries[row_index * col_len + col_index] = vector_get_min(vec);
684 obstack_free(&pbqp->obstack, vec);
688 pbqp_edge *edge = get_edge(pbqp, src_node->index, tgt_node->index);
690 /* Disconnect node. */
691 disconnect_edge(src_node, src_edge);
692 disconnect_edge(tgt_node, tgt_edge);
694 /* Add node to back propagation list. */
695 node_bucket_insert(&reduced_bucket, node);
698 edge = alloc_edge(pbqp, src_node->index, tgt_node->index, mat);
700 pbqp_matrix_add(edge->costs, mat);
702 /* Free local matrix. */
703 obstack_free(&pbqp->obstack, mat);
705 reorder_node(src_node);
706 reorder_node(tgt_node);
709 if (pbqp->dump_file) {
710 fputs("<br>\nAfter reduction:<br>\n", pbqp->dump_file);
711 dump_edge(pbqp->dump_file, edge);
714 /* Edge has changed so we simplify it. */
715 simplify_edge(pbqp, edge);
718 static void select_alternative(pbqp_node *node, unsigned selected_index)
724 unsigned max_degree = pbqp_node_get_degree(node);
727 node->solution = selected_index;
728 node_vec = node->costs;
729 node_len = node_vec->len;
730 assert(selected_index < node_len);
732 /* Set all other costs to infinity. */
733 for (node_index = 0; node_index < node_len; ++node_index) {
734 if (node_index != selected_index) {
735 node_vec->entries[node_index].data = INF_COSTS;
739 /* Add all incident edges to edge bucket, since they are now independent. */
740 for (edge_index = 0; edge_index < max_degree; ++edge_index) {
741 insert_into_edge_bucket(node->edges[edge_index]);
745 static pbqp_node *get_node_with_max_degree(void)
747 pbqp_node **bucket = node_buckets[3];
748 unsigned bucket_len = node_bucket_get_length(bucket);
749 unsigned bucket_index;
750 unsigned max_degree = 0;
751 pbqp_node *result = NULL;
753 for (bucket_index = 0; bucket_index < bucket_len; ++bucket_index) {
754 pbqp_node *candidate = bucket[bucket_index];
755 unsigned degree = pbqp_node_get_degree(candidate);
757 if (degree > max_degree) {
766 static unsigned get_local_minimal_alternative(pbqp *pbqp, pbqp_node *node)
773 unsigned max_degree = 0;
776 unsigned min_index = 0;
782 node_vec = node->costs;
783 node_len = node_vec->len;
785 for (node_index = 0; node_index < node_len; ++node_index) {
786 num value = node_vec->entries[node_index].data;
788 for (edge_index = 0; edge_index < max_degree; ++edge_index) {
789 edge = node->edges[edge_index];
791 is_src = edge->src == node;
794 vec = vector_copy(pbqp, edge->tgt->costs);
795 vector_add_matrix_row(vec, mat, node_index);
797 vec = vector_copy(pbqp, edge->src->costs);
798 vector_add_matrix_col(vec, mat, node_index);
801 value = pbqp_add(value, vector_get_min(vec));
803 obstack_free(&pbqp->obstack, vec);
808 min_index = node_index;
815 void apply_RN(pbqp *pbqp)
817 pbqp_node *node = NULL;
818 unsigned min_index = 0;
822 /* We want to reduce a node with maximum degree. */
823 node = get_node_with_max_degree();
825 assert(pbqp_node_get_degree(node) > 2);
827 if (pbqp->dump_file) {
829 sprintf(txt, "RN-Reduction of Node n%d", node->index);
830 dump_section(pbqp->dump_file, 2, txt);
831 pbqp_dump_graph(pbqp);
834 min_index = get_local_minimal_alternative(pbqp, node);
836 if (pbqp->dump_file) {
837 fprintf(pbqp->dump_file, "node n%d is set to %d<br><br>\n",
838 node->index, min_index);
841 /* Now that we found the local minimum set all other costs to infinity. */
842 select_alternative(node, min_index);
845 static void apply_brute_force_reductions(pbqp *pbqp)
848 if (edge_bucket_get_length(edge_bucket) > 0) {
850 } else if (node_bucket_get_length(node_buckets[1]) > 0) {
852 } else if (node_bucket_get_length(node_buckets[2]) > 0) {
854 } else if (node_bucket_get_length(node_buckets[3]) > 0) {
855 apply_Brute_Force(pbqp);
862 static unsigned get_minimal_alternative(pbqp *pbqp, pbqp_node *node)
867 unsigned min_index = 0;
869 unsigned bucket_index;
873 node_vec = node->costs;
874 node_len = node_vec->len;
875 bucket_index = node->bucket_index;
877 for (node_index = 0; node_index < node_len; ++node_index) {
878 pbqp_node_bucket bucket_deg3;
880 unsigned bucket_0_length;
881 unsigned bucket_red_length;
883 node_bucket_init(&bucket_deg3);
885 /* Some node buckets and the edge bucket should be empty. */
886 assert(node_bucket_get_length(node_buckets[1]) == 0);
887 assert(node_bucket_get_length(node_buckets[2]) == 0);
888 assert(edge_bucket_get_length(edge_bucket) == 0);
890 /* char *tmp = obstack_finish(&pbqp->obstack); */
892 /* Save current PBQP state. */
893 node_bucket_copy(&bucket_deg3, node_buckets[3]);
894 node_bucket_shrink(&node_buckets[3], 0);
895 node_bucket_deep_copy(pbqp, &node_buckets[3], bucket_deg3);
896 node_bucket_update(pbqp, node_buckets[3]);
897 bucket_0_length = node_bucket_get_length(node_buckets[0]);
898 bucket_red_length = node_bucket_get_length(reduced_bucket);
900 /* Select alternative and solve PBQP recursively. */
901 select_alternative(node_buckets[3][bucket_index], node_index);
902 apply_brute_force_reductions(pbqp);
904 value = determine_solution(pbqp->dump_file);
908 min_index = node_index;
911 /* Some node buckets and the edge bucket should still be empty. */
912 assert(node_bucket_get_length(node_buckets[1]) == 0);
913 assert(node_bucket_get_length(node_buckets[2]) == 0);
914 assert(edge_bucket_get_length(edge_bucket) == 0);
916 /* Clear modified buckets... */
917 node_bucket_shrink(&node_buckets[3], 0);
919 /* ... and restore old PBQP state. */
920 node_bucket_shrink(&node_buckets[0], bucket_0_length);
921 node_bucket_shrink(&reduced_bucket, bucket_red_length);
922 node_bucket_copy(&node_buckets[3], bucket_deg3);
923 node_bucket_update(pbqp, node_buckets[3]);
926 /* obstack_free(&pbqp->obstack, tmp); */
927 node_bucket_free(&bucket_deg3);
933 void apply_Brute_Force(pbqp *pbqp)
935 pbqp_node *node = NULL;
936 unsigned min_index = 0;
940 /* We want to reduce a node with maximum degree. */
941 node = get_node_with_max_degree();
943 assert(pbqp_node_get_degree(node) > 2);
945 if (pbqp->dump_file) {
947 sprintf(txt, "BF-Reduction of Node n%d", node->index);
948 dump_section(pbqp->dump_file, 2, txt);
949 pbqp_dump_graph(pbqp);
952 min_index = get_minimal_alternative(pbqp, node);
953 node = pbqp->nodes[node->index];
955 if (pbqp->dump_file) {
956 fprintf(pbqp->dump_file, "node n%d is set to %d<br><br>\n",
957 node->index, min_index);
960 /* Now that we found the minimum set all other costs to infinity. */
961 select_alternative(node, min_index);
964 void solve_pbqp_brute_force(pbqp *pbqp)
966 /* Reduce nodes degree ... */
967 initial_simplify_edges(pbqp);
969 /* ... and put node into bucket representing their degree. */
970 fill_node_buckets(pbqp);
972 apply_brute_force_reductions(pbqp);
974 pbqp->solution = determine_solution(pbqp->dump_file);
976 //printf("solution: %lld\n", pbqp->solution);
978 /* Solve reduced nodes. */
979 back_propagate(pbqp);
984 void back_propagate_RI(pbqp *pbqp, pbqp_node *node)
995 edge = node->edges[0];
997 is_src = edge->src == node;
1004 /* Update pointer for brute force solver. */
1005 other = pbqp->nodes[other->index];
1007 vector_add_matrix_col(vec, mat, other->solution);
1012 /* Update pointer for brute force solver. */
1013 other = pbqp->nodes[other->index];
1015 vector_add_matrix_row(vec, mat, other->solution);
1018 node->solution = vector_get_min_index(vec);
1019 if (pbqp->dump_file) {
1020 fprintf(pbqp->dump_file, "node n%d is set to %d<br>\n", node->index, node->solution);
1024 void back_propagate_RII(pbqp *pbqp, pbqp_node *node)
1026 pbqp_edge *src_edge = node->edges[0];
1027 pbqp_edge *tgt_edge = node->edges[1];
1028 int src_is_src = src_edge->src == node;
1029 int tgt_is_src = tgt_edge->src == node;
1030 pbqp_matrix *src_mat;
1031 pbqp_matrix *tgt_mat;
1032 pbqp_node *src_node;
1033 pbqp_node *tgt_node;
1042 src_node = src_edge->tgt;
1044 src_node = src_edge->src;
1048 tgt_node = tgt_edge->tgt;
1050 tgt_node = tgt_edge->src;
1053 /* Swap nodes if necessary. */
1054 if (tgt_node->index < src_node->index) {
1055 pbqp_node *tmp_node;
1056 pbqp_edge *tmp_edge;
1058 tmp_node = src_node;
1059 src_node = tgt_node;
1060 tgt_node = tmp_node;
1062 tmp_edge = src_edge;
1063 src_edge = tgt_edge;
1064 tgt_edge = tmp_edge;
1066 src_is_src = src_edge->src == node;
1067 tgt_is_src = tgt_edge->src == node;
1070 /* Update pointer for brute force solver. */
1071 src_node = pbqp->nodes[src_node->index];
1072 tgt_node = pbqp->nodes[tgt_node->index];
1074 src_mat = src_edge->costs;
1075 tgt_mat = tgt_edge->costs;
1077 node_vec = node->costs;
1079 row_index = src_node->solution;
1080 col_index = tgt_node->solution;
1082 vec = vector_copy(pbqp, node_vec);
1085 vector_add_matrix_col(vec, src_mat, row_index);
1087 vector_add_matrix_row(vec, src_mat, row_index);
1091 vector_add_matrix_col(vec, tgt_mat, col_index);
1093 vector_add_matrix_row(vec, tgt_mat, col_index);
1096 node->solution = vector_get_min_index(vec);
1097 if (pbqp->dump_file) {
1098 fprintf(pbqp->dump_file, "node n%d is set to %d<br>\n", node->index, node->solution);
1101 obstack_free(&pbqp->obstack, vec);
1104 int node_is_reduced(pbqp_node *node)
1106 if (!reduced_bucket) return 0;
1108 if (pbqp_node_get_degree(node) == 0) return 1;
1110 return node_bucket_contains(reduced_bucket, node);