summaryrefslogtreecommitdiffstats
path: root/src/sat/satoko/solver_api.c
blob: 0193b1c32bb34279772e67d6eb43fa47b820ec14 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
//===--- solver_api.h -------------------------------------------------------===
//
//                     satoko: Satisfiability solver
//
// This file is distributed under the BSD 2-Clause License.
// See LICENSE for details.
//
//===------------------------------------------------------------------------===
#include <stdio.h>
#include <assert.h>
#include <string.h>
#include <math.h>

#include "act_var.h"
#include "solver.h"
#include "utils/misc.h"

#include "misc/util/abc_global.h"
ABC_NAMESPACE_IMPL_START

//===------------------------------------------------------------------------===
// Satoko internal functions
//===------------------------------------------------------------------------===
static inline void solver_rebuild_order(solver_t *s)
{
    unsigned var;
    vec_uint_t *vars = vec_uint_alloc(vec_char_size(s->assigns));

    for (var = 0; var < vec_char_size(s->assigns); var++)
        if (var_value(s, var) == SATOKO_VAR_UNASSING)
            vec_uint_push_back(vars, var);
    heap_build(s->var_order, vars);
    vec_uint_free(vars);
}

static inline int clause_is_satisfied(solver_t *s, struct clause *clause)
{
    unsigned i;
    unsigned *lits = &(clause->data[0].lit);
    for (i = 0; i < clause->size; i++)
        if (lit_value(s, lits[i]) == SATOKO_LIT_TRUE)
            return SATOKO_OK;
    return SATOKO_ERR;
}

static inline void solver_clean_stats(solver_t *s)
{
    long n_conflicts_all = s->stats.n_conflicts_all;
    long n_propagations_all = s->stats.n_propagations_all;
    memset(&(s->stats), 0, sizeof(struct satoko_stats));
    s->stats.n_conflicts_all = n_conflicts_all;
    s->stats.n_propagations_all = n_propagations_all;
}

static inline void print_opts(solver_t *s)
{
    printf( "+-[ BLACK MAGIC - PARAMETERS ]-+\n");
    printf( "|                              |\n");
    printf( "|--> Restarts heuristic        |\n");
    printf( "|    * LBD Queue   = %6d    |\n", s->opts.sz_lbd_bqueue);
    printf( "|    * Trail Queue = %6d    |\n", s->opts.sz_trail_bqueue);
    printf( "|    * f_rst       = %6.2f    |\n", s->opts.f_rst);
    printf( "|    * b_rst       = %6.2f    |\n", s->opts.b_rst);
    printf( "|                              |\n");
    printf( "|--> Clause DB reduction:      |\n");
    printf( "|    * First       = %6d    |\n", s->opts.n_conf_fst_reduce);
    printf( "|    * Inc         = %6d    |\n", s->opts.inc_reduce);
    printf( "|    * Special Inc = %6d    |\n", s->opts.inc_special_reduce);
    printf( "|    * Protected (LBD) < %2d    |\n", s->opts.lbd_freeze_clause);
    printf( "|                              |\n");
    printf( "|--> Binary resolution:        |\n");
    printf( "|    * Clause size < %3d       |\n", s->opts.clause_max_sz_bin_resol);
    printf( "|    * Clause lbd  < %3d       |\n", s->opts.clause_min_lbd_bin_resol);
    printf( "+------------------------------+\n\n");
}

static inline void print_stats(solver_t *s)
{
    printf("starts        : %10d\n", s->stats.n_starts);
    printf("conflicts     : %10ld\n", s->stats.n_conflicts);
    printf("decisions     : %10ld\n", s->stats.n_decisions);
    printf("propagations  : %10ld\n", s->stats.n_propagations);
}

//===------------------------------------------------------------------------===
// Satoko external functions
//===------------------------------------------------------------------------===
solver_t * satoko_create()
{
    solver_t *s = satoko_calloc(solver_t, 1);

    satoko_default_opts(&s->opts);
    s->status = SATOKO_OK;
    /* User data */
    s->assumptions = vec_uint_alloc(0);
    s->final_conflict = vec_uint_alloc(0);
    /* Clauses Database */
    s->all_clauses = cdb_alloc(0);
    s->originals = vec_uint_alloc(0);
    s->learnts = vec_uint_alloc(0);
    s->watches = vec_wl_alloc(0);
    /* Activity heuristic */
    s->var_act_inc = VAR_ACT_INIT_INC;
    s->clause_act_inc = CLAUSE_ACT_INIT_INC;
    /* Variable Information */
    s->activity = vec_act_alloc(0);
    s->var_order = heap_alloc(s->activity);
    s->levels = vec_uint_alloc(0);
    s->reasons = vec_uint_alloc(0);
    s->assigns = vec_char_alloc(0);
    s->polarity = vec_char_alloc(0);
    /* Assignments */
    s->trail = vec_uint_alloc(0);
    s->trail_lim = vec_uint_alloc(0);
    /* Temporary data used by Search method */
    s->bq_trail = b_queue_alloc(s->opts.sz_trail_bqueue);
    s->bq_lbd = b_queue_alloc(s->opts.sz_lbd_bqueue);
    s->n_confl_bfr_reduce = s->opts.n_conf_fst_reduce;
    s->RC1 = 1;
    s->RC2 = s->opts.n_conf_fst_reduce;
    /* Temporary data used by Analyze */
    s->temp_lits = vec_uint_alloc(0);
    s->seen = vec_char_alloc(0);
    s->tagged = vec_uint_alloc(0);
    s->stack = vec_uint_alloc(0);
    s->last_dlevel = vec_uint_alloc(0);
    /* Misc temporary */
    s->stamps = vec_uint_alloc(0);
    return s;
}

void satoko_destroy(solver_t *s)
{
    vec_uint_free(s->assumptions);
    vec_uint_free(s->final_conflict);
    cdb_free(s->all_clauses);
    vec_uint_free(s->originals);
    vec_uint_free(s->learnts);
    vec_wl_free(s->watches);
    vec_act_free(s->activity);
    heap_free(s->var_order);
    vec_uint_free(s->levels);
    vec_uint_free(s->reasons);
    vec_char_free(s->assigns);
    vec_char_free(s->polarity);
    vec_uint_free(s->trail);
    vec_uint_free(s->trail_lim);
    b_queue_free(s->bq_lbd);
    b_queue_free(s->bq_trail);
    vec_uint_free(s->temp_lits);
    vec_char_free(s->seen);
    vec_uint_free(s->tagged);
    vec_uint_free(s->stack);
    vec_uint_free(s->last_dlevel);
    vec_uint_free(s->stamps);
    if (s->marks)
        vec_char_free(s->marks);
    satoko_free(s);
}

void satoko_default_opts(satoko_opts_t *opts)
{
    memset(opts, 0, sizeof(satoko_opts_t));
    opts->verbose = 0;
    opts->no_simplify = 0;
    /* Limits */
    opts->conf_limit = 0;
    opts->prop_limit  = 0;
    /* Constants used for restart heuristic */
    opts->f_rst = 0.8;
    opts->b_rst = 1.4;
    opts->fst_block_rst   = 10000;
    opts->sz_lbd_bqueue   = 50;
    opts->sz_trail_bqueue = 5000;
    /* Constants used for clause database reduction heuristic */
    opts->n_conf_fst_reduce = 2000;
    opts->inc_reduce = 300;
    opts->inc_special_reduce = 1000;
    opts->lbd_freeze_clause = 30;
    opts->learnt_ratio = 0.5;
    /* VSIDS heuristic */
    opts->var_act_limit = VAR_ACT_LIMIT;
    opts->var_act_rescale = VAR_ACT_RESCALE;
    opts->var_decay = 0.95;
    opts->clause_decay = (clause_act_t) 0.995;
    /* Binary resolution */
    opts->clause_max_sz_bin_resol = 30;
    opts->clause_min_lbd_bin_resol = 6;

    opts->garbage_max_ratio = (float) 0.3;
}

/**
 * TODO: sanity check on configuration options
 */
void satoko_configure(satoko_t *s, satoko_opts_t *user_opts)
{
    assert(user_opts);
    memcpy(&s->opts, user_opts, sizeof(satoko_opts_t));
}

int satoko_simplify(solver_t * s)
{
    unsigned i, j = 0;
    unsigned cref;

    assert(solver_dlevel(s) == 0);
    if (solver_propagate(s) != UNDEF)
        return SATOKO_ERR;
    if (s->n_assigns_simplify == vec_uint_size(s->trail) || s->n_props_simplify > 0)
        return SATOKO_OK;

    vec_uint_foreach(s->originals, cref, i) {
        struct clause *clause = clause_fetch(s, cref);

    if (clause_is_satisfied(s, clause)) {
            clause->f_mark = 1;
            s->stats.n_original_lits -= clause->size;
            clause_unwatch(s, cref);
        } else
            vec_uint_assign(s->originals, j++, cref);
    }
    vec_uint_shrink(s->originals, j);
    solver_rebuild_order(s);
    s->n_assigns_simplify = vec_uint_size(s->trail);
    s->n_props_simplify = s->stats.n_original_lits + s->stats.n_learnt_lits;
    return SATOKO_OK;
}

void satoko_setnvars(solver_t *s, int nvars)
{
    int i;
    for (i = satoko_varnum(s); i < nvars; i++)
        satoko_add_variable(s, 0);
}

int satoko_add_variable(solver_t *s, char sign)
{
    unsigned var = vec_act_size(s->activity);
    vec_wl_push(s->watches);
    vec_wl_push(s->watches);
    vec_act_push_back(s->activity, 0);
    vec_uint_push_back(s->levels, 0);
    vec_char_push_back(s->assigns, SATOKO_VAR_UNASSING);
    vec_char_push_back(s->polarity, sign);
    vec_uint_push_back(s->reasons, UNDEF);
    vec_uint_push_back(s->stamps, 0);
    vec_char_push_back(s->seen, 0);
    heap_insert(s->var_order, var);
    if (s->marks)
        vec_char_push_back(s->marks, 0);
    return var;
}

int satoko_add_clause(solver_t *s, int *lits, int size)
{
    unsigned i, j;
    unsigned prev_lit;
    unsigned max_var;
    unsigned cref;

    qsort((void *) lits, size, sizeof(unsigned), stk_uint_compare);
    max_var = lit2var(lits[size - 1]);
    while (max_var >= vec_act_size(s->activity))
        satoko_add_variable(s, SATOKO_LIT_FALSE);

    vec_uint_clear(s->temp_lits);
    j = 0;
    prev_lit = UNDEF;
    for (i = 0; i < (unsigned)size; i++) {
        if ((unsigned)lits[i] == lit_compl(prev_lit) || lit_value(s, lits[i]) == SATOKO_LIT_TRUE)
            return SATOKO_OK;
        else if ((unsigned)lits[i] != prev_lit && var_value(s, lit2var(lits[i])) == SATOKO_VAR_UNASSING) {
            prev_lit = lits[i];
            vec_uint_push_back(s->temp_lits, lits[i]);
        }
    }

    if (vec_uint_size(s->temp_lits) == 0) {
        s->status = SATOKO_ERR;
        return SATOKO_ERR;
    } if (vec_uint_size(s->temp_lits) == 1) {
        solver_enqueue(s, vec_uint_at(s->temp_lits, 0), UNDEF);
        return (s->status = (solver_propagate(s) == UNDEF));
    }
    if ( 0 ) {
        for ( i = 0; i < vec_uint_size(s->temp_lits); i++ ) {
            int lit = vec_uint_at(s->temp_lits, i);
            printf( "%s%d ", lit&1 ? "!":"", lit>>1 );
        }
        printf( "\n" );
    }
    cref = solver_clause_create(s, s->temp_lits, 0);
    clause_watch(s, cref);
    return SATOKO_OK;
}

void satoko_assump_push(solver_t *s, int lit)
{
    assert(lit2var(lit) < (unsigned)satoko_varnum(s));
    // printf("[Satoko] Push assumption: %d\n", lit);
    vec_uint_push_back(s->assumptions, lit);
    vec_char_assign(s->polarity, lit2var(lit), lit_polarity(lit));
}

void satoko_assump_pop(solver_t *s)
{
    assert(vec_uint_size(s->assumptions) > 0);
    // printf("[Satoko] Pop assumption: %d\n", vec_uint_pop_back(s->assumptions));
    vec_uint_pop_back(s->assumptions);
    solver_cancel_until(s, vec_uint_size(s->assumptions));
}

int satoko_solve(solver_t *s)
{
    int status = SATOKO_UNDEC;

    assert(s);
    solver_clean_stats(s);
    //if (s->opts.verbose)
    //    print_opts(s);
    if (s->status == SATOKO_ERR) {
        printf("Satoko in inconsistent state\n");
        return SATOKO_UNDEC;
    }

    if (!s->opts.no_simplify)
        if (satoko_simplify(s) != SATOKO_OK)
            return SATOKO_UNDEC;

    while (status == SATOKO_UNDEC) {
        status = solver_search(s);
        if (solver_check_limits(s) == 0 || solver_stop(s))
            break;
        if (s->nRuntimeLimit && Abc_Clock() > s->nRuntimeLimit)
            break;
        if (s->pFuncStop && s->pFuncStop(s->RunId))
            break;
    }
    if (s->opts.verbose)
        print_stats(s);
    
    solver_cancel_until(s, vec_uint_size(s->assumptions));
    return status;
}

int satoko_solve_assumptions(solver_t *s, int * plits, int nlits)
{
    int i, status;
    // printf("\n[Satoko] Solve with assumptions.. (%d)\n", vec_uint_size(s->assumptions));
    // printf("[Satoko]   + Variables: %d\n", satoko_varnum(s));
    // printf("[Satoko]   + Clauses: %d\n", satoko_clausenum(s));
    // printf("[Satoko]   + Trail size: %d\n", vec_uint_size(s->trail));
    // printf("[Satoko]   + Queue head: %d\n", s->i_qhead);
    // solver_debug_check_trail(s);
    for ( i = 0; i < nlits; i++ )
        satoko_assump_push( s, plits[i] );
    status = satoko_solve( s );
    for ( i = 0; i < nlits; i++ )
        satoko_assump_pop( s );
    return status;
}

int satoko_solve_assumptions_limit(satoko_t *s, int * plits, int nlits, int nconflim)
{
    int temp = s->opts.conf_limit, status;
    s->opts.conf_limit = nconflim ? s->stats.n_conflicts + nconflim : 0;
    status = satoko_solve_assumptions(s, plits, nlits);
    s->opts.conf_limit = temp;
    return status;
}
int satoko_minimize_assumptions(satoko_t * s, int * plits, int nlits, int nconflim)
{
    int i, nlitsL, nlitsR, nresL, nresR, status;
    if ( nlits == 1 )
    {
        // since the problem is UNSAT, we try to solve it without assuming the last literal
        // if the result is UNSAT, the last literal can be dropped; otherwise, it is needed
        status = satoko_solve_assumptions_limit( s, NULL, 0, nconflim );
        return (int)(status != SATOKO_UNSAT); // return 1 if the problem is not UNSAT
    }
    assert( nlits >= 2 );
    nlitsL = nlits / 2;
    nlitsR = nlits - nlitsL;
    // assume the left lits
    for ( i = 0; i < nlitsL; i++ )
        satoko_assump_push(s, plits[i]);
    // solve with these assumptions
    status = satoko_solve_assumptions_limit( s, NULL, 0, nconflim );
    if ( status == SATOKO_UNSAT ) // these are enough
    {
        for ( i = 0; i < nlitsL; i++ )
            satoko_assump_pop(s);
        return satoko_minimize_assumptions( s, plits, nlitsL, nconflim );
    }
    // these are not enoguh
    // solve for the right lits
    nresL = nlitsR == 1 ? 1 : satoko_minimize_assumptions( s, plits + nlitsL, nlitsR, nconflim );
    for ( i = 0; i < nlitsL; i++ )
        satoko_assump_pop(s);
    // swap literals
    vec_uint_clear(s->temp_lits);
    for ( i = 0; i < nlitsL; i++ )
        vec_uint_push_back(s->temp_lits, plits[i]);
    for ( i = 0; i < nresL; i++ )
        plits[i] = plits[nlitsL+i];
    for ( i = 0; i < nlitsL; i++ )
        plits[nresL+i] = vec_uint_at(s->temp_lits, i);
    // assume the right lits
    for ( i = 0; i < nresL; i++ )
        satoko_assump_push(s, plits[i]);
    // solve with these assumptions
    status = satoko_solve_assumptions_limit( s, NULL, 0, nconflim );
    if ( status == SATOKO_UNSAT ) // these are enough
    {
        for ( i = 0; i < nresL; i++ )
            satoko_assump_pop(s);
        return nresL;
    }
    // solve for the left lits
    nresR = nlitsL == 1 ? 1 : satoko_minimize_assumptions( s, plits + nresL, nlitsL, nconflim );
    for ( i = 0; i < nresL; i++ )
        satoko_assump_pop(s);
    return nresL + nresR;
}

int satoko_final_conflict(solver_t *s, int **out)
{
    *out = (int *)vec_uint_data(s->final_conflict);
    return vec_uint_size(s->final_conflict);
}

satoko_stats_t * satoko_stats(satoko_t *s)
{
    return &s->stats;
}

satoko_opts_t * satoko_options(satoko_t *s)
{
    return &s->opts;
}

void satoko_bookmark(satoko_t *s)
{
    // printf("[Satoko] Bookmark.\n");
    assert(s->status == SATOKO_OK);
    assert(solver_dlevel(s) == 0);
    s->book_cl_orig = vec_uint_size(s->originals);
    s->book_cl_lrnt = vec_uint_size(s->learnts);
    s->book_vars = vec_char_size(s->assigns);
    s->book_trail = vec_uint_size(s->trail);
    // s->book_qhead = s->i_qhead;
    s->opts.no_simplify = 1;
}

void satoko_unbookmark(satoko_t *s)
{
    // printf("[Satoko] Unbookmark.\n");
    assert(s->status == SATOKO_OK);
    s->book_cl_orig = 0;
    s->book_cl_lrnt = 0;
    s->book_cdb = 0;
    s->book_vars = 0;
    s->book_trail = 0;
    // s->book_qhead = 0;
    s->opts.no_simplify = 0;
}

void satoko_reset(satoko_t *s)
{
    // printf("[Satoko] Reset.\n");
    vec_uint_clear(s->assumptions);
    vec_uint_clear(s->final_conflict);
    cdb_clear(s->all_clauses);
    vec_uint_clear(s->originals);
    vec_uint_clear(s->learnts);
    vec_wl_clean(s->watches);
    vec_act_clear(s->activity);
    heap_clear(s->var_order);
    vec_uint_clear(s->levels);
    vec_uint_clear(s->reasons);
    vec_char_clear(s->assigns);
    vec_char_clear(s->polarity);
    vec_uint_clear(s->trail);
    vec_uint_clear(s->trail_lim);
    b_queue_clean(s->bq_lbd);
    b_queue_clean(s->bq_trail);
    vec_uint_clear(s->temp_lits);
    vec_char_clear(s->seen);
    vec_uint_clear(s->tagged);
    vec_uint_clear(s->stack);
    vec_uint_clear(s->last_dlevel);
    vec_uint_clear(s->stamps);
    s->status = SATOKO_OK;
    s->var_act_inc = VAR_ACT_INIT_INC;
    s->clause_act_inc = CLAUSE_ACT_INIT_INC;
    s->n_confl_bfr_reduce = s->opts.n_conf_fst_reduce;
    s->RC1 = 1;
    s->RC2 = s->opts.n_conf_fst_reduce;
    s->book_cl_orig = 0;
    s->book_cl_lrnt = 0;
    s->book_cdb = 0;
    s->book_vars = 0;
    s->book_trail = 0;
    s->i_qhead = 0;
}

void satoko_rollback(satoko_t *s)
{
    unsigned i, cref;
    unsigned n_originals = vec_uint_size(s->originals) - s->book_cl_orig;
    unsigned n_learnts = vec_uint_size(s->learnts) - s->book_cl_lrnt;
    struct clause **cl_to_remove;

    // printf("[Satoko] rollback.\n");
    assert(s->status == SATOKO_OK);
    assert(solver_dlevel(s) == 0);
    if (!s->book_vars) {
        satoko_reset(s);
        return;
    }
    cl_to_remove = satoko_alloc(struct clause *, n_originals + n_learnts);
    /* Mark clauses */
    vec_uint_foreach_start(s->originals, cref, i, s->book_cl_orig)
        cl_to_remove[i] = clause_fetch(s, cref);
    vec_uint_foreach_start(s->learnts, cref, i, s->book_cl_lrnt)
        cl_to_remove[n_originals + i] = clause_fetch(s, cref);
    for (i = 0; i < n_originals + n_learnts; i++) {
        clause_unwatch(s, cdb_cref(s->all_clauses, (unsigned *)cl_to_remove[i]));
        cl_to_remove[i]->f_mark = 1;
    }
    satoko_free(cl_to_remove);
    vec_uint_shrink(s->originals, s->book_cl_orig);
    vec_uint_shrink(s->learnts, s->book_cl_lrnt);
    /* Shrink variable related vectors */
    for (i = s->book_vars; i < 2 * vec_char_size(s->assigns); i++) {
        vec_wl_at(s->watches, i)->size = 0;
        vec_wl_at(s->watches, i)->n_bin = 0;
    }
    // s->i_qhead = s->book_qhead;
    s->watches->size = s->book_vars;
    vec_act_shrink(s->activity, s->book_vars);
    vec_uint_shrink(s->levels, s->book_vars);
    vec_uint_shrink(s->reasons, s->book_vars);
    vec_uint_shrink(s->stamps, s->book_vars);
    vec_char_shrink(s->assigns, s->book_vars);
    vec_char_shrink(s->seen, s->book_vars);
    vec_char_shrink(s->polarity, s->book_vars);
    solver_rebuild_order(s);
    /* Rewind solver and cancel level 0 assignments to the trail */
    solver_cancel_until(s, 0);
    vec_uint_shrink(s->trail, s->book_trail);
    if (s->book_cdb)
        s->all_clauses->size = s->book_cdb;
    s->book_cl_orig = 0;
    s->book_cl_lrnt = 0;
    s->book_vars = 0;
    s->book_trail = 0;
    // s->book_qhead = 0;
}

void satoko_mark_cone(satoko_t *s, int * pvars, int n_vars)
{
    int i;
    if (!solver_has_marks(s))
        s->marks = vec_char_init(satoko_varnum(s), 0);
    for (i = 0; i < n_vars; i++) {
        var_set_mark(s, pvars[i]);
        vec_sdbl_assign(s->activity, pvars[i], 0);
        if (!heap_in_heap(s->var_order, pvars[i]))
            heap_insert(s->var_order, pvars[i]);
    }
}

void satoko_unmark_cone(satoko_t *s, int *pvars, int n_vars)
{
    int i;
    assert(solver_has_marks(s));
    for (i = 0; i < n_vars; i++)
        var_clean_mark(s, pvars[i]);
}

void satoko_write_dimacs(satoko_t *s, char *fname, int wrt_lrnt, int zero_var)
{
    FILE *file;
    unsigned i;
    unsigned n_vars = vec_act_size(s->activity);
    unsigned n_orig = vec_uint_size(s->originals) + vec_uint_size(s->trail);
    unsigned n_lrnts = vec_uint_size(s->learnts);
    unsigned *array;

    assert(wrt_lrnt == 0 || wrt_lrnt == 1);
    assert(zero_var == 0 || zero_var == 1);
    if (fname != NULL)
        file = fopen(fname, "w");
    else
        file = stdout;
    
    if (file == NULL) {
        printf( "Error: Cannot open output file.\n");
        return;
    }
    fprintf(file, "p cnf %d %d\n", n_vars, wrt_lrnt ? n_orig + n_lrnts : n_orig);
    for (i = 0; i < vec_char_size(s->assigns); i++) {
        if ( var_value(s, i) != SATOKO_VAR_UNASSING ) {
            if (zero_var)
                fprintf(file, "%d\n", var_value(s, i) == SATOKO_LIT_FALSE ? -(int)(i) : i);
            else
                fprintf(file, "%d 0\n", var_value(s, i) == SATOKO_LIT_FALSE ? -(int)(i + 1) : i + 1);
        }
    }
    array = vec_uint_data(s->originals);
    for (i = 0; i < vec_uint_size(s->originals); i++)
        clause_dump(file, clause_fetch(s, array[i]), !zero_var);
    
    if (wrt_lrnt) {
        array = vec_uint_data(s->learnts);
        for (i = 0; i < n_lrnts; i++)
            clause_dump(file, clause_fetch(s, array[i]), !zero_var);
    }
    fclose(file);

}

int satoko_varnum(satoko_t *s)
{
    return vec_char_size(s->assigns);
}

int satoko_clausenum(satoko_t *s)
{
    return vec_uint_size(s->originals);
}

int satoko_learntnum(satoko_t *s)
{
    return vec_uint_size(s->learnts);
}

int satoko_conflictnum(satoko_t *s)
{
    return satoko_stats(s)->n_conflicts_all;
}

void satoko_set_stop(satoko_t *s, int * pstop)
{
    s->pstop = pstop;
}

void satoko_set_stop_func(satoko_t *s, int (*fnct)(int))
{
    s->pFuncStop = fnct;
}

void satoko_set_runid(satoko_t *s, int id)
{
    s->RunId = id;
}

int satoko_read_cex_varvalue(satoko_t *s, int ivar)
{
    return satoko_var_polarity(s, ivar) == SATOKO_LIT_TRUE;
}

abctime satoko_set_runtime_limit(satoko_t* s, abctime Limit)
{
    abctime nRuntimeLimit = s->nRuntimeLimit;
    s->nRuntimeLimit = Limit;
    return nRuntimeLimit;
}

char satoko_var_polarity(satoko_t *s, unsigned var)
{
    return vec_char_at(s->polarity, var);
}

ABC_NAMESPACE_IMPL_END