C++ ExpressionNode::getRight方法代码示例

ExpressionNode BinaryOperation::simplify(ExpressionNode& left)
{
	if (left.getRight() > 0)
	{
		if ((left.getRight())->getRight() != 0)
		{
			throw ExpressionNode::WrongArityError("> 2 arguments for BinaryOperation");
		}
		return simplify(left, *left.getRight());
	}
	else
	{
		throw ExpressionNode::WrongArityError("only 1 argument for BinaryOperation"); 
	}
}

ExpressionNode::ExpressionNode(const ExpressionNode & other): //copy constructor
type(other.getType()), operation(other.getOperation()), activechildren(other.getOperation()->getArity()),
right(0), firstChild(0), variable(other.getVariable()), value(other.getValue())
{
	setRight(other.getRight());
	setFirstChild(other.getFirstChild()); // automatically also sets other children
}

ExpressionNode* ExpressionNode::findParentOf(const ExpressionNode& target)
{
	ExpressionNode * currentNode = this;
	std::stack <ExpressionNode*> nodeStack;
	ExpressionNode * parent = 0;
	
	while (true)
	{
		if (currentNode != 0)
		{
			if (currentNode == &target)
			{
				return parent;
			}
			nodeStack.push(currentNode);
			parent = currentNode;
			currentNode = currentNode->getFirstChild();
		}
		if (nodeStack.size() == 1) // only root left in stack
		{
			// target not found
			throw TargetNotFoundError();
		}
		currentNode = nodeStack.top();
		nodeStack.pop();
		currentNode = currentNode->getRight();
	}
	
}

bool ExpressionNode::operator== (const ExpressionNode& other) const
{
	ExpressionNode *selfptr;
	ExpressionNode *otherptr;
	
	if (getType() == other.getType() && 
		getOperation() == other.getOperation() && 
		getVariable() == other.getVariable() &&
		getValue() == other.getValue() )
	{
		selfptr = firstChild;
		otherptr = other.getFirstChild();
		while (selfptr != 0 && otherptr != 0)
		{
			if (*selfptr == *otherptr)
			{
				selfptr = selfptr->getRight();
				otherptr = otherptr->getRight();
			}
			else
			{
				return false;
			}
		}
		if (selfptr == 0 && otherptr == 0)
		{
			return true;
		}
		else
		{
			assert(selfptr != otherptr);
			return false;
		}
	}
	else
	{	
		return false;
	}
}

ExpressionNode BinaryOperation::simplify(const ExpressionNode& root) const
{
	ExpressionNode* left = root.getFirstChild();
	if (left != 0)
	{
		if (left->getRight() != 0)
		{
			if ((left->getRight())->getRight() != 0)
			{
				throw ExpressionNode::WrongArityError("> 2 arguments for BinaryOperation");
			}
			return simplify( *left, *(left->getRight()) );
		}
		else
		{
			cerr << left << endl;
			throw ExpressionNode::WrongArityError("only 1 argument for BinaryOperation"); 
		}
	}
	else
	{
		throw ExpressionNode::WrongArityError("No arguments for BinaryOperation");
	}
}

std::ostream& operator<<(std::ostream& out, const ExpressionNode& node)
{
	ExpressionNode * ptr = 0;
	
	if (node.getType() == OPERATION)
	{
		if (node.getOperation() == 0)
		{
			if (node.getFirstChild() != 0)
			{
				throw ExpressionNode::GenericError("ERROR: inserting OPERATION parent node w/o operation into ostream");
			}
			else
			{
				out << "()";
				return out;
			}		
		}
		if (node.getOperation()->isFuncFormat() == true)
		{
			out << *(node.getOperation()) << "(";
			ptr = node.getFirstChild();
			if (ptr != 0)
			{
				out << *ptr;
				ptr = ptr->getRight();
				while (ptr != 0)
				{
					out << ", " << *ptr;
					ptr = ptr->getRight();
				}
			}
			out << ")";
		}
		else
		{
			out << "(";
			ptr = node.getFirstChild();
			if (ptr != 0)
			{
				out << *ptr;
				ptr = ptr->getRight();
				while (ptr != 0)
				{
					out << *(node.getOperation()) << *ptr;
					ptr = ptr->getRight();
				}
			}
			out << ")";
		}
	}
	else if (node.getType() == VARIABLE)
	{
		if (node.getVariable() == 0)
		{
			throw ExpressionNode::GenericError("ERROR: inserting VARIABLE node w/o variable into ostream");
		}
		out << *(node.getVariable());
	}
	else
	{
		if (node.getType() != NUMBER)
		{
			int i = node.getType();
			std::clog << std::endl << i << std::endl;
		}
		assert(node.getType() == NUMBER);
		out << node.getValue();
	}
	return out;
}

ExpressionNode Addition::addTerms(const ExpressionNode& term1, const ExpressionNode& term2) const
{
	clog << "checkpoint addTerms" << endl;
	
	Number coefficient1;
	Number coefficient2;
	const ExpressionNode * varpart1;
	const ExpressionNode * varpart2;
	ExpressionNode * left;
	ExpressionNode * right;
	ExpressionNode newRight;
	ExpressionNode newCoef;
	ExpressionNode newNode;
	
	if (term1.getType() == NUMBER)
	{
		coefficient1 = term1.getValue();
		varpart1 = 0;
	}
	else if (term1.getType() == OPERATION)
	{
		if (term1.getOperation() == &MULTIPLICATION)
		{
			left = term1.getFirstChild();
			right = left->getRight();
			if (left->getType() == NUMBER)
			{
				coefficient1 = left->getValue();
				varpart1 = right;
			}
			else if (right->getType() == NUMBER)
			{
				coefficient1 = right->getValue();
				varpart1 = left;
			}
			else
			{
				coefficient1 = MULTIPLICATION.getIdentity();
				varpart1 = &term1;
			}
		}
		else
		{
			coefficient1 = MULTIPLICATION.getIdentity();
			varpart1 = &term1;
		}
	}
	else // VARIABLE
	{
		assert(term1.getType() == VARIABLE);
		coefficient1 = MULTIPLICATION.getIdentity();
		varpart1 = &term1;
	}
	
	if (term2.getType() == NUMBER)
	{
		coefficient2 = term2.getValue();
		varpart2 = 0;
	}
	else if (term2.getType() == OPERATION)
	{
		if (term2.getOperation() == &MULTIPLICATION)
		{
			left = term2.getFirstChild();
			right = left->getRight();
			if (left->getType() == NUMBER)
			{
				coefficient2 = left->getValue();
				varpart2 = right;
			}
			else if (right->getType() == NUMBER)
			{
				coefficient2 = right->getValue();
				varpart2 = left;
			}
			else
			{
				coefficient2 = MULTIPLICATION.getIdentity();
				varpart2 = &term2;
			}
		}
		else
		{
			coefficient2 = MULTIPLICATION.getIdentity();
			varpart2 = &term2;
		}
	}
	else // VARIABLE
	{
		assert(term2.getType() == VARIABLE);
		coefficient2 = MULTIPLICATION.getIdentity();
		varpart2 = &term2;
	}
	
	if (varpart1 != 0 && varpart2 != 0)
	{
		if (*varpart1 == *varpart2)
		{
			clog << "addTerms simplify like terms" << endl
				<< "coef1: " << coefficient1 << " var1: " << *varpart1 << endl
//.........这里部分代码省略.........