prefix

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Postfix
{
    class Program
    {
        public static int cnt = 0;
        static double Add(double a, double b)
        {
            if (a > 0 && b > 0)
            {
                cnt++;
            }
            return a + b;
        }
        static double Substract(double a, double b)
        {
            return a - b;
        }
        static double Multiply(double a, double b)
        {
            return a * b;
        }
        static double Divide(double a, double b)
        {
            return a / b;
        }

        delegate double MyDelegate(double a, double b);
        static double Evaluate(List<string> tokens)
        {
            IDictionary<string, MyDelegate> dict = new Dictionary<string, MyDelegate>
            {
                {"+",Add},
                {"-",Substract},
                {"*",Multiply},
                {"/",Divide}
            };

            Stack<double> stack = new Stack<double>();
            foreach (var token in tokens)
            {
                try
                {
                    stack.Push(double.Parse(token));
                }
                catch (Exception)
                {
                    double op1 = stack.Pop();
                    double op2 = stack.Pop();

                    stack.Push(dict[token](op1, op2));
                }
            }
            return stack.Pop();

        }
        static void Main(string[] args)
        {
            List<string> list = new List<string>();
            for (int i = 0; i < args.Length; i++)
            {
                list.Add(args[i]);
            }
            list.Reverse();
            Evaluate(list);
            Console.WriteLine(cnt);

        }
    }
}