static void Main(string[] args)
{
Console.WriteLine("Example: ");
MathTree tree = new MathTree(new MathTreeNode(new MathSymbol(MathSymbol.Operator.Add)));
tree.root.right = new MathTreeNode(new MathSymbol(MathSymbol.Operator.Add));
tree.root.right.right = new MathTreeNode(new MathSymbol(MathSymbol.Operator.Multiply));
tree.root.right.right.right = new MathTreeNode(new MathSymbol(4));
tree.root.right.right.left = new MathTreeNode(new MathSymbol(3));
tree.root.right.left = new MathTreeNode(new MathSymbol(2));
tree.root.left = new MathTreeNode(new MathSymbol(1));
Console.WriteLine(": " + String.Join(" ", tree.ToPreOrderString().ToCharArray()));
Console.WriteLine("=> " + tree.Evaluate());
while (true)
{
Console.Write(": ");
string input = Console.ReadLine();
try
{
tree = MathTree.FromString(input);
Console.WriteLine("=> " + tree.Evaluate());
}
catch (InvalidOperationException e)
{
Console.WriteLine("Error: " + e.Message);
}
}
}
