mass.Sort();

struct ExpertMark
    {
        public int first;
        public double sec;
        public double thr;
        public string four;
    }

    class Delphi
    {
        private double mediana;
        private double max;
        private double min;
        private int index;
        private double kvartul;
        private double foot_lim;
        private double head_lim;
        private double dov_interval;
        private ArrayList mass;

        public  Delphi()
        {
            mass = new ArrayList();
        }



        public void addData(ExpertMark value)
        {
            mass.Add(value);
        }
                   
        public  double serGrouoMark()
        {
            double sum = 0;
            for (int i = 0; i < mass.Count; i++)
            {
                ExpertMark mark = (ExpertMark)mass[i];

                sum += mark.first;
            }
            sum = sum / mass.Count;
            return sum;

        }

        public double serPos()
        {
            double sum = 0;
            for (int i = 1; i < mass.Count; i++)
            {
                ExpertMark mark = (ExpertMark)mass[i];
                sum += mark.sec;

            }
            sum = sum / mass.Count;
            return sum;
        }

        public double serPop()
        {
            double sum = 0;
            for (int i = 1; i < mass.Count - 1; i++)
            {
                
                ExpertMark mark = (ExpertMark)mass[i];
                sum += mark.first * mark.sec;
               

            }

            sum = sum / mass.Count;
            return sum;
        }

        public void SortMass()
        {           
            mass.Sort();
            this.index = (mass.Count / 2) - 1;
            this.min = Convert.ToDouble(mass[0].ToString());
            this.max = Convert.ToDouble(mass[mass.Count - 1].ToString());
        }