public Operand[] GetExpression(Queue <string> rpnQueue)
{
var stack = new Stack <Operand>();
while (rpnQueue.Count > 0)
{
var s = rpnQueue.Dequeue();
if (decimal.TryParse(s, out var d))
{
stack.Push(new Operand {
Type = OperandType.Constant, Value = d
});
}
else if (operators.Contains(s))
{
var op1 = stack.Pop();
var op2 = stack.Pop();
var opType = OperationType.FromValue <OperationType>(s);
if (opType == OperationType.Substract)
{
op1.Value = -op1.Value;
opType = OperationType.Add;
}
if (op1.Operation?.OperationType == opType)
{
op1.Operation.Operands.Add(op2);
stack.Push(op1);
}
else if (op2.Operation?.OperationType == opType)
{
op2.Operation.Operands.Add(op1);
stack.Push(op2);
}
else
{
var op = new Operand
{
Type = OperandType.Operation,
Operation = new Operation
{
OperationType = opType,
Operands = new List <Operand> {
op2, op1
}
},
Value = 1
};
stack.Push(op);
}
}
else
{
stack.Push(new Operand {
Type = OperandType.Variable, Name = s, Value = 1
});
}
}
return(stack.ToArray());
}