public static BooleanExpression FindMininalExpressionForBinary(BooleanExpression targetBinary, BooleanFunction f,
List <BooleanExpression> availableExpressions)
{
var queue = new ImprovisedPriorityQueue <BooleanExpression>(20);
var knownTruthTables = new HashSet <byte>();
var knownExpressions = new HashSet <BooleanExpression>();
foreach (var expression in availableExpressions)
{
queue.TryEnqueue(expression, 1);
}
while (queue.Count != 0)
{
var curExperession = queue.Dequeue();
byte truthTable = curExperession.Eval();
if (knownTruthTables.Contains(truthTable))
{
continue;
}
if ((curExperession.Eval() & 0xAA) == (targetBinary.Eval() & 0xAA))
{
return(curExperession);
}
knownExpressions.Add(curExperession);
knownTruthTables.Add(truthTable);
foreach (var anotherExpression in knownExpressions)
{
foreach (var thirdExpression in knownExpressions)
{
foreach (var neighbourExpression in CombineTertiary(f, curExperession, anotherExpression, thirdExpression))
{
queue.TryEnqueue(neighbourExpression, neighbourExpression.CountOps());
}
}
}
}
throw new CouldntFindExpressionException();
}
public override byte Eval()
{
byte aVal = Left.Eval();
byte bVal = Right.Eval();
int res;
switch (Op)
{
case BooleanOperation.Zero:
res = 0x00;
break;
case BooleanOperation.NOR:
res = ~(aVal | bVal);
break;
case BooleanOperation.CoImp:
res = aVal & ~bVal;
break;
case BooleanOperation.NotA:
res = ~aVal;
break;
case BooleanOperation.BCoImp:
res = ~aVal & bVal;
break;
case BooleanOperation.NotB:
res = ~bVal;
break;
case BooleanOperation.Xor:
res = aVal ^ bVal;
break;
case BooleanOperation.NAND:
res = ~(aVal & bVal);
break;
case BooleanOperation.And:
res = aVal & bVal;
break;
case BooleanOperation.Eq:
res = aVal ^ (~bVal);
break;
case BooleanOperation.B:
res = bVal;
break;
case BooleanOperation.BImp:
res = aVal | ~bVal;
break;
case BooleanOperation.A:
res = aVal;
break;
case BooleanOperation.Imp:
res = ~aVal | bVal;
break;
case BooleanOperation.Or:
res = aVal | bVal;
break;
case BooleanOperation.One:
res = 0xFF;
break;
default:
throw new ArgumentException();
}
return((byte)res);
}
public static BooleanExpression FindMininalExpressionForBinary(BooleanExpression targetBinary, BooleanFunction f,
List<BooleanExpression> availableExpressions)
{
var queue = new ImprovisedPriorityQueue<BooleanExpression>(20);
var knownTruthTables = new HashSet<byte>();
var knownExpressions = new HashSet<BooleanExpression>();
foreach(var expression in availableExpressions) {
queue.TryEnqueue(expression, 1);
}
while(queue.Count != 0) {
var curExperession = queue.Dequeue();
byte truthTable = curExperession.Eval();
if(knownTruthTables.Contains(truthTable)) {
continue;
}
if((curExperession.Eval() & 0xAA) == (targetBinary.Eval() & 0xAA)) {
return curExperession;
}
knownExpressions.Add(curExperession);
knownTruthTables.Add(truthTable);
foreach(var anotherExpression in knownExpressions) {
foreach(var thirdExpression in knownExpressions) {
foreach(var neighbourExpression in CombineTertiary(f, curExperession, anotherExpression, thirdExpression)) {
queue.TryEnqueue(neighbourExpression, neighbourExpression.CountOps());
}
}
}
}
throw new CouldntFindExpressionException();
}