/// <summary>
/// Runs the thing.
/// </summary>
internal static void Run()
{
var five = new BinaryAddOperation(2, 3);
Console.WriteLine(five.Operand() + " 5");
var ten = new BinaryMultiplyOperation(five, 2);
Console.WriteLine(ten.Operand() + " 10");
var negativeFour = new UnarySubtractOperation(4);
Console.WriteLine(negativeFour.Operand() + " -4");
var four = new UnarySubtractOperation(negativeFour);
Console.WriteLine(four.Operand() + " 4");
Console.WriteLine();
Console.WriteLine(new BinaryAddOperation(3, new BinaryMultiplyOperation(4, 5)).Operand() + " 23");
Console.WriteLine(new BinaryMultiplyOperation(new BinaryAddOperation(2, 3), 4).Operand() + " 20");
Console.WriteLine();
// 2*3+(4-2)*2
Console.WriteLine(new BinaryAddOperation(new BinaryMultiplyOperation(2, 3), new BinaryMultiplyOperation(new BinarySubtractOperation(4, 2), 2)).Operand() + " 10");
// 2*(2*2)*2
Console.WriteLine(new BinaryMultiplyOperation(new BinaryMultiplyOperation(2, new BinaryMultiplyOperation(2, 2)), 2).Operand() + " 16");
// 1+(2+(3+4)+5)+6
Console.WriteLine(new BinaryAddOperation(new BinaryAddOperation(1, new BinaryAddOperation(new BinaryAddOperation(2, new BinaryAddOperation(3, 4)), 5)), 6).Operand() + " 21");
// 1+(2-(3+4)+5)+6
Console.WriteLine(new BinaryAddOperation(new BinaryAddOperation(1, new BinaryAddOperation(new BinarySubtractOperation(2, new BinaryAddOperation(3, 4)), 5)), 6).Operand() + " 7");
// 1+(2+(3+4)-5)+6
Console.WriteLine(new BinaryAddOperation(new BinaryAddOperation(1, new BinarySubtractOperation(new BinaryAddOperation(2, new BinaryAddOperation(3, 4)), 5)), 6).Operand() + " 11");
// ABCDEFGHIJKLMOP
// 1+(2+(3+4)*5)+6
// O B A E D K H G I L P
Console.WriteLine(new BinaryAddOperation(new BinaryAddOperation(1, new BinaryAddOperation(2, new BinaryMultiplyOperation(new BinaryAddOperation(3, 4), 5))), 6).Operand() + " 44");
// ABCDEFGHIJKLMOP
// 1+(2+(3+4)*5)+6
// B A O E D K H G I L P
Console.WriteLine(new BinaryAddOperation(1, new BinaryAddOperation(new BinaryAddOperation(2, new BinaryMultiplyOperation(new BinaryAddOperation(3, 4), 5)), 6)).Operand() + " 44");
Console.WriteLine();
Console.WriteLine(Evaluator.Evaluate("2+3") + " 5");
Console.WriteLine(Evaluator.Evaluate("2+3+5") + " 10");
Console.WriteLine(Evaluator.Evaluate("2+3+5+10+10") + " 30");
Console.WriteLine();
foreach (var token in Tokenize("2+3"))
{
Console.WriteLine(token);
}
}
/// <summary>
/// Evaluates the <paramref name="expr" /> into a <see cref="Double" /> value.
/// </summary>
/// <param name="expr">The <see cref="String" /> to evaluate.</param>
/// <returns>The <paramref name="expr" /> as a <see cref="Double" />.</returns>
public static double? Evaluate(string expr)
{
var multi = expr.Split('+').Select(Convert.ToDouble).ToList();
Operation operation = new BinaryAddOperation(multi[0], multi[1]);
for (var i = 2; i < multi.Count; i++)
{
operation = operation.Add(new UnaryAddOperation(multi[i]));
}
return Convert.ToDouble(operation.Operand().ToString());
}