static private Result BCRecursive(KnowledgeBase knowledgeBase, string target)
{
List <Clause> statements = knowledgeBase.InConclusion(target);
List <string> symbolsEntailed = new List <string>();
List <bool> results = new List <bool>();
foreach (Clause c in statements)
{
bool result = true;
foreach (string s in c.Premise)
{
Result r = BCRecursive(knowledgeBase, s);
result &= r.Success;
if (r.Success)
{
symbolsEntailed = r.Symbols;
}
}
results.Add(result);
if (!symbolsEntailed.Contains(c.Conclusion))
{
symbolsEntailed.Add(c.Conclusion);
}
}
return(new Result(results.All(r => r) && results.Count != 0, symbols: symbolsEntailed));
}
static private short BCRecursive(KnowledgeBase knowledgeBase, string target, List <Sentence> sentencesChecked, ref List <string> symbolsEntailed)
{
List <Sentence> statements = knowledgeBase.InConclusion(target);
short results = 0;
foreach (Sentence c in statements)
{
if (!sentencesChecked.Contains(c))
{
sentencesChecked.Add(c);
short result = 1;
foreach (string s in c.Premise)
{
List <Sentence> sentencesCheckedCopy = new List <Sentence>(sentencesChecked);
short r = BCRecursive(knowledgeBase, s, sentencesCheckedCopy, ref symbolsEntailed);
result = r;
if (r != 1)
{
break; // can break out of loop cause all statements must be true
}
}
if (!symbolsEntailed.Contains(c.Conclusion))
{
symbolsEntailed.Add(c.Conclusion);
}
if (result != 0)
{
results = result;
}
else
{
break;
}
}
else if (results == 0)
{
results = -1; // to indicate overflow on branch so no inference can be drawn from it
}
}
return(results);
}
