using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        var input = new Queue<string>("( 1 + 2 ) * 3 ^ 4".Split(' '));

        Console.WriteLine(AddSubtract(input));

    }

    private static double AddSubtract(Queue<string> tokens)

    {

        var value = MultiplyDivide(tokens);

        while(tokens.Count > 0 && tokens.Peek() is "+" or "-")

        {

            var op = tokens.Dequeue();

            var next = MultiplyDivide(tokens);

            value = op is "+" ? value + next : value - next;

        }

        return value;

    }

    private static double MultiplyDivide(Queue<string> tokens)

    {

        var value = Power(tokens);

        while(tokens.Count > 0 && tokens.Peek() is "*" or "/")

        {

            var op = tokens.Dequeue();

            var next = Power(tokens);

            value = op is "*" ? value * next : value / next;

        }

        return value;

    }

    private static double Power(Queue<string> tokens)

    {

        var value = Unary(tokens);

        if(tokens.Count > 0 && tokens.Peek() is "^")

        {

            tokens.Dequeue();

            value = Math.Pow(value, Power(tokens));

        }

        return value;

    }

    private static double Unary(Queue<string> tokens)

    {

        if(tokens.Peek() is "-")

        {

            tokens.Dequeue();

            return -Unary(tokens);

        }

        return Const(tokens);

    }

    private static double Const(Queue<string> tokens)

    {

        if(tokens.Peek() is "(")

        {

            tokens.Dequeue();

            var value = AddSubtract(tokens);

            tokens.Dequeue();

            return value;

        }

        return double.Parse(tokens.Dequeue());

    }

}