public static ExpressionNode CalculateTree(ExpressionNode[] nodes)
{
if (nodes.Length == 0)
return null;
if (nodes.Length == 1) return nodes[0];
if (nodes.Length == 2) return new CombineNode(nodes[0], nodes[1], nodes[1].Operator);
var president = int.MaxValue;
for (var i = 1; i < nodes.Length; i++)
{
var filter = nodes[i];
var sortIndex = getOperatorIndex(filter.Operator);
if (sortIndex < president) president = sortIndex;
}
var index = 0;
var op = '+';
for (index = 1; index < nodes.Length; index++)
{
var filter = nodes[index];
if (getOperatorIndex(filter.Operator) == president)
{
op = filter.Operator;
break;
}
}
var a = CalculateTree(nodes.Take(index).ToArray());
var b = CalculateTree(nodes.Skip(index).ToArray());
return new CombineNode(a, b, op);
}
private static ValueList CalculateSpaceList(ExpressionNode[] nodes)
{
var result = new ValueList();
var skip = 0;
for (var i = 1; i < nodes.Length; i++)
{
var filter = nodes[i];
if (filter.Operator == ' ')
{
var a = CalculateList(nodes.Skip(skip).Take(i - skip).ToArray());
result.Add(a);
skip = i;
}
}
result.Add(CalculateList(nodes.Skip(skip).ToArray()));
return result;
}