BOOL res_HasTautology(CLAUSE clause)
/**********************************************************
INPUT: A clauses.
RETURNS: TRUE if the clause contains a complementary
literal pair and FALSE otherwise.
CAUTION: None.
***********************************************************/
{
BOOL found;
TERM literal1;
int i, j, n;
found = FALSE;
n = clause_Length(clause);
for (i = 0; i < n && !found; i++) {
literal1 = fol_ComplementaryTerm(clause_GetLiteralTerm(clause,i));
for (j = 0; j < n && !found; j++)
if (j != i && term_Equal(literal1, clause_GetLiteralTerm(clause,j)))
found = TRUE;
term_Delete(literal1);
}
return found;
}
LIST cond_CondFast(CLAUSE c)
/**********************************************************
INPUT: A clause c.
RETURNS: A list with indexes with respect to c that can
be deleted due to condensing.
CAUTION: None.
***********************************************************/
{
int vec, i, j, k;
LIST indexlist;
indexlist = list_Nil();
vec = vec_ActMax();
for (i = 0; i < clause_Length(c); i++) {
vec_Push((POINTER) i);
}
for (k = clause_Length(c) - 1; k >= 0; k--) {
for (i = vec; i < vec_ActMax(); i++) {
if ((int)vec_GetNth(i) != k) {
cont_StartBinding();
if (unify_Match(cont_LeftContext(),
clause_GetLiteralTerm(c,k),
clause_GetLiteralTerm(c,(int)vec_GetNth(i)))) {
cont_BackTrack();
for (j = vec; j < vec_ActMax(); j++) {
if (k == (int)vec_GetNth(j)) {
vec_Swap((vec_ActMax() -1) ,j);
j = vec_ActMax();
}
}
if (subs_IdcRes(c,vec,(vec_ActMax() -1))) {
indexlist = list_Cons((POINTER)k,indexlist);
vec_Pop();
}
i = vec_ActMax()+1;
}
else
cont_BackTrack();
}
}
}
vec_SetMax(vec);
return indexlist;
}
BOOL res_BackSubWithLength(CLAUSE clause, st_INDEX stindex)
/**********************************************************
INPUT: A clauses and an index.
RETURNS: TRUE if a clause of the index subsumes the clause clause
and length(clause) >= length(clause of index).
CAUTION: None.
***********************************************************/
{
int n,i;
LIST scan,generals;
TERM term;
LITERAL litres;
n = clause_Length(clause);
for (i = 0; i < n; i++) {
term = clause_GetLiteralTerm(clause,i);
generals = st_GetGen(cont_LeftContext(), stindex, term);
for (scan = generals; !list_Empty(scan); scan = list_Cdr(scan)) {
litres = (LITERAL) list_Car(scan);
if (litres == clause_GetLiteral(clause_LiteralOwningClause(litres),0) &&
clause_Length(clause) >= clause_Length(clause_LiteralOwningClause(litres)) &&
clause_Weight(clause) >= clause_Weight(clause_LiteralOwningClause(litres)) &&
subs_Idc(clause_LiteralOwningClause(litres),clause)) {
list_Delete(generals);
return TRUE;
}
}
list_Delete(generals);
}
return FALSE;
}
void res_InsertClauseIndex(CLAUSE clause, st_INDEX stindex)
/**********************************************************
INPUT: A st_INDEX and a clause.
RETURNS: Inserts the clause in the st_INDEX stindex.
CAUTION: None.
***********************************************************/
{
int n,j;
n = clause_Length(clause);
for (j = 0; j < n; j++)
st_EntryCreate(stindex,
clause_GetLiteral(clause,j),
clause_GetLiteralTerm(clause,j),
cont_LeftContext());
}
void res_DeleteClauseIndex(CLAUSE clause, st_INDEX stindex)
/**********************************************************
INPUT: A st_INDEX and a clause.
RETURNS: Deletes the clause from the st_INDEX stindex.
CAUTION: None.
***********************************************************/
{
int n, j;
n = clause_Length(clause);
for (j = 0; j < n; j++)
if (!st_EntryDelete(stindex,
clause_GetLiteral(clause,j),
clause_GetLiteralTerm(clause,j),
cont_LeftContext()))
misc_DumpCore();
}