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

namespace Exam1
{
    class School
    {
        private string name;
        private List<Student> students;

        public School (string name)
        {
            this.name = name;
            this.students = new List<Student>();
        }

        public School()
        {
        }

        public string Name
        {
            get
            {
                return name;
            }
            set
            {
                name = value;
            }
        }

        public List<Student> Students
        {
            get
            {
                return students;
            }
            set
            {
                students = value;
            }
        }

        public void AddStudent (string name, double grade)
        {
            Student student = new Student(name, grade);
            students.Add(student);
        }

        public double AverageResultInRange(int start, int end)
        {
            double sum = 0;
            int count = 0;
            for (int index = start; index <= end; index++)
            {
                sum += students[index].Grade;
                count++;
            }

            return sum / count;
        }

        public List<string> RemoveStudentsByGrade(double grade)
        {
            List<String> leftStudents = new List<String>();
            foreach (Student student in students)
            {
               if(student.Grade < grade)
                {
                    leftStudents.Add(student.Name);
                }
            }
            return leftStudents;
        }

        public List<Student> SortAscendingByName()
        {
            List<Student> sorted = students.OrderBy(s => s.Name).ToList();
            students = sorted;
            return sorted;
        }

        public List<Student> SortDescendingByGrade()
        {
            List<Student> sorted = students.OrderByDescending(s => s.Grade).ToList();
            students = sorted;
            return sorted;
        }

        public bool CheckStudentIsInSchool(string name)
        {
            foreach (Student student in students)
            {
                if (student.Name == name)
                {
                    return true;
                }
            }

            return false;
        }

        public string[] ProvideInformationAboutAllStudents()
        {
            List<string> infoList = new List<string>();
            foreach(Student student in students)
            {
                infoList.Add(student.ToString());
            }
            return infoList.ToArray();
        }



    }
}