static int
do_search(struct saucy *s)
{
int min;
unprepare_permutation(s);
/* Backtrack to the ancestor with zeta */
if (s->lev > s->anc) s->lev = s->anc + 1;
/* Perform additional backtracking */
min = backtrack(s);
/* Keep going while there are tree nodes to expand */
while (s->lev) {
/* Descend to a new leaf node */
if (descend(s, &s->right, s->start[s->lev], min)
&& descend_left(s)) {
/* Prepare permutation */
prepare_permutation(s);
/* If we found an automorphism, return it */
if (s->is_automorphism(s)) {
++s->stats->gens;
s->stats->support += s->ndiffs;
update_theta(s);
return s->consumer(s->n, s->gamma,
s->ndiffs, s->unsupp, s->arg);
}
else {
unprepare_permutation(s);
}
}
/* If we get here, something went wrong; backtrack */
++s->stats->bads;
min = backtrack_bad(s);
}
/* Normalize group size */
while (s->stats->grpsize_base >= 10.0) {
s->stats->grpsize_base /= 10;
++s->stats->grpsize_exp;
}
return 0;
}
int *
saucy_search(void)
{
int i;
/* Do initialization steps if necessary */
if (!init) {
init = 1;
/* Initialize stats */
stats->grpsize_base = 1.0;
stats->grpsize_exp = stats->nodes = stats->bads = stats->gens = 0;
/* Preprocessing after initial coloring */
refine();
}
/* Keep going while there are tree nodes to expand */
while (lev) {
if (desc) { desc = 0; descend(); }
/* Find a target cell */
++stats->nodes; target_cell();
if (target != n+1) { descend_left(); continue; }
/* We don't have a target, so we're discrete */
if (!have_zeta) {
have_zeta = 1;
for (i = 0; i < n; ++i) zeta[lab[i]] = i;
if (canon != NULL) memcpy(canon, lab, n * sizeof(int));
}
else {
/* Prepare permutation and check */
for (i = 0; i < n; ++i) gamma[i] = lab[zeta[i]];
is_automorphism();
/* Do some stuff if we actually got an automorphism */
if (flag) {
++stats->gens;
update_theta();
}
/* Keep track of leaf nodes that are not automorphisms */
else {
++stats->bads;
}
}
/* Since we're discrete, we need to backtrack */
backtrack(stats); desc = 1;
if (flag) return gamma;
}
/* Normalize group size */
while (stats->grpsize_base >= 10.0) {
stats->grpsize_base /= 10;
++stats->grpsize_exp;
}
/* All done */
return NULL;
}
