void QEvalInstrucGenerator::appendEdgeQueryOnePath(std::queue<QEvalInstruc> &instrucQueue, const QueryData &qData, arg_idx_t argIdx, std::vector<bool> &qtClausePushed)
{
	std::stack<q_clause_idx_t> qClauseStack;
	std::stack<arg_idx_t> targetVarArgIdxStack;
	NonRepQueue<arg_idx_t> holdVarArgIdxQueue;
	holdVarArgIdxQueue.push(argIdx);
	while (!holdVarArgIdxQueue.empty()) {
		arg_idx_t current = holdVarArgIdxQueue.front();
		for (q_clause_idx_t i = 0; i < (int)qData.numClauses(); i++) {
			if (!qtClausePushed[i]) {
				const QEvalClause * clausePtr = qData.getQEvalClause(i);
				const std::set<arg_idx_t> &refVarArgIdxSet = clausePtr->inVarArgIdxSet;
				assert (refVarArgIdxSet.size() == 2);
				if (*(refVarArgIdxSet.begin()) == current) {
					holdVarArgIdxQueue.push(*(refVarArgIdxSet.end()));
				}
				else {
					holdVarArgIdxQueue.push(*(refVarArgIdxSet.begin()));
				}
				qClauseStack.push(i);
				targetVarArgIdxStack.push(current);
				qtClausePushed[i] = true;
			}
		}
		holdVarArgIdxQueue.pop();
	}
	while (!qClauseStack.empty()) {
		instrucQueue.push(QEvalInstruc(qClauseStack.top(), targetVarArgIdxStack.top()));
		qClauseStack.pop();
		targetVarArgIdxStack.pop();
	}
}
void QEvalInstrucGenerator::appendIndepQueryInstruc(std::queue<QEvalInstruc> &instrucQueue, const QueryData &qData, std::vector<bool> &qClausePushed)
{
	for (q_clause_idx_t i = 0; i < (int)qData.numClauses(); i++) {
		const QEvalClause * clausePtr = qData.getQEvalClause(i);
		if (clausePtr->inVarArgIdxSet.size() == 0) {
			instrucQueue.push(QEvalInstruc(i, 0));
			qClausePushed[i] = true;
		}
	}
}
void QEvalInstrucGenerator::generate(std::queue<QEvalInstruc> &instrucQueue, const QueryData &qData)
{
	std::vector<bool> qClausePushed(qData.numClauses());
	// first append all independent query clauses to the instruction queue
	appendIndepQueryInstruc(instrucQueue, qData, qClausePushed);

	// second append all boolean node select
	appendNodeQueryInstruc(instrucQueue, qData, qClausePushed);

	// third append all boolean edge select
	appendEdgeQueryInstruc(instrucQueue, qData, qClausePushed);
}