/// <summary>
/// Xor brekdown
/// </summary>
/// <param name="node"></param>
/// <returns></returns>
public static bool XOR(ref BoolExpr node)
{
if (node.Op == OperatorType.XOR)
{
var oldNode = node;
var copyLeft = BoolExprFactory.CreateCopy(node.Left);
var copyRight = BoolExprFactory.CreateCopy(node.Right);
var negatedLeft = new BoolExprNegation(copyLeft);
var negatedRight = new BoolExprNegation(copyRight);
copyLeft.Parent = negatedLeft;
copyRight.Parent = negatedRight;
var left = new BoolExprConjunction(node.Left, negatedRight);
node.Left.Parent = left;
negatedRight.Parent = left;
var right = new BoolExprConjunction(negatedLeft, node.Right);
negatedLeft.Parent = right;
node.Right.Parent = right;
node = new BoolExprDisjunction(left, right);
node.Parent = oldNode.Parent;
left.Parent = node;
right.Parent = node;
UpdateParent(node, oldNode);
return(true);
}
return(false);
}
/// <summary>
/// DeMorgan's Law
/// </summary>
/// <param name="node"></param>
/// <returns></returns>
public static bool DeM(ref BoolExpr node)
{
if (node.Op == OperatorType.NOT)
{
if (node.Right.Op == OperatorType.AND)
{
var oldNode = node;
var temp = node.Right;
var left = new BoolExprNegation(temp.Left);
var right = new BoolExprNegation(temp.Right);
node = new BoolExprDisjunction(left, right);
node.Parent = oldNode.Parent;
left.Parent = node;
right.Parent = node;
UpdateParent(node, oldNode);
return(true);
}
else if (node.Right.Op == OperatorType.OR)
{
var oldNode = node;
var temp = node.Right;
var left = new BoolExprNegation(temp.Left);
var right = new BoolExprNegation(temp.Right);
node = new BoolExprConjunction(left, right);
node.Parent = oldNode.Parent;
left.Parent = node;
right.Parent = node;
UpdateParent(node, oldNode);
return(true);
}
}
return(false);
}
/// <summary>
/// Implication rule
/// </summary>
/// <param name="node"></param>
/// <returns></returns>
public static bool Implication(ref BoolExpr node)
{
if (node.Op == OperatorType.CONDITIONAL)
{
var oldNode = node;
var left = new BoolExprNegation(node.Left);
var right = node.Right;
node = new BoolExprDisjunction(left, right);
node.Parent = oldNode.Parent;
left.Parent = node;
right.Parent = node;
UpdateParent(node, oldNode);
return(true);
}
return(false);
}
