public OpExpression(BooleanOperation op, BooleanExpression left, BooleanExpression right)
{
Op = op;
Left = left;
Right = right;
}
public OpExpression(BooleanOperation op, BooleanVariable left, BooleanVariable right)
{
Op = op;
Left = new VarExpression(left);
Right = new VarExpression(right);
}
public bool Equals(BooleanExpression obj)
{
return ToString() == obj.ToString();
}
public IEnumerable<BooleanExpression> CombineWith(BooleanExpression anotherExpression,
BooleanOperation[] ops)
{
foreach(var op in ops) {
yield return new OpExpression(op, Clone(), anotherExpression.Clone());
yield return new OpExpression(op, anotherExpression.Clone(), Clone());
}
}
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 static IEnumerable<TertiaryOpExpression> CombineTertiary(BooleanFunction f,
BooleanExpression firstExpression, BooleanExpression anotherExpression, BooleanExpression thirdExpression)
{
yield return new TertiaryOpExpression(f, firstExpression.Clone(), anotherExpression.Clone(),
thirdExpression.Clone());
yield return new TertiaryOpExpression(f, firstExpression.Clone(), thirdExpression.Clone(),
anotherExpression.Clone());
yield return new TertiaryOpExpression(f, anotherExpression.Clone(), firstExpression.Clone(),
thirdExpression.Clone());
yield return new TertiaryOpExpression(f, thirdExpression.Clone(), firstExpression.Clone(),
anotherExpression.Clone());
yield return new TertiaryOpExpression(f, anotherExpression.Clone(), thirdExpression.Clone(),
firstExpression.Clone());
yield return new TertiaryOpExpression(f, thirdExpression.Clone(), anotherExpression.Clone(),
firstExpression.Clone());
}
public TertiaryOpExpression(BooleanFunction f, BooleanExpression first, BooleanExpression second, BooleanExpression third)
{
F = f;
First = first;
Second = second;
Third = third;
}