CompanyRoster

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

namespace _04.CompanyRoster
{
    public class CompanyRoster
    {
        public static void Main(string[] args)
        {
            HashSet<string> departments = new HashSet<string>();
            List<Employee> employees = new List<Employee>();
            int n = int.Parse(Console.ReadLine());
            for (int i = 0; i < n; i++)
            {
                string[] tokens = Console.ReadLine()
                    .Split(new char[] { ' ', '\t', '\n' }, StringSplitOptions.RemoveEmptyEntries);
                string name = tokens[0];
                decimal salary = decimal.Parse(tokens[1]);
                string position = tokens[2];
                string department = tokens[3];
                Employee emp = new Employee(name, salary, position, department);
                if (tokens.Length == 5)
                {
                    if (tokens[4].Contains("@"))
                    {
                        emp.email = tokens[4];
                    }
                    else
                    {
                        int age;
                        bool isNumber = int.TryParse(tokens[4], out age);
                        if (isNumber)
                        {
                            emp.age = age;
                        }
                    }
                }
                else if (tokens.Length == 6)
                {
                    emp.email = tokens[4];
                    emp.age = int.Parse(tokens[5]);
                }
                employees.Add(emp);
                departments.Add(department);
            }
            decimal avgMaxSalary = 0;
            string maxSalaryDepartment = string.Empty;
            foreach (var dep in departments)
            {
                decimal avgSalary = 0;
                int emps = 0;
                foreach (var emp in employees)
                {
                    if (emp.department == dep)
                    {
                        emps++;
                        avgSalary += emp.salary;
                    }
                }
                avgSalary /= emps;
                if (avgSalary > avgMaxSalary)
                {
                    avgMaxSalary = avgSalary;
                    maxSalaryDepartment = dep;
                }
            }
            Console.WriteLine("Highest Average Salary: {0}", maxSalaryDepartment);
            employees = employees
                .Where(emp => emp.department == maxSalaryDepartment)
                .OrderByDescending(emp => emp.salary)
                .ToList();
            foreach (var emp in employees)
            {
                Console.WriteLine("{0} {1:F2} {2} {3}",
                    emp.name, emp.salary, emp.email, emp.age);
            }
        }
    }

    public class Employee
    {
        public string name;
        public decimal salary;
        public string position;
        public string department;
        public string email { get; set; }
        public int age { get; set; }

        public Employee(string name, decimal salary,
            string position, string department)
        {
            this.name = name;
            this.salary = salary;
            this.position = position;
            this.department = department;
            this.email = "n/a";
            this.age = -1;
        }
    }
}