using System;

namespace c
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("**Welcome to use number operators**");
            Console.WriteLine("Please select one of the operators");
            Console.WriteLine("");
            int option=0;
            do
            {
                Console.WriteLine();
                Console.WriteLine("1.Sum, 2. Greatest common divisor, 3. Sort in descending, 4.Exit. Input 1~4:");
                option = Convert.ToInt32(Console.ReadLine());
                if (option == 1)
                {
                    Console.WriteLine();
                    Console.Write("Input integer numbers with \",\" ");
                    string[] input = Console.ReadLine().Split(',');
                    int[] input1 = Array.ConvertAll<string, int>(input, s => int.Parse(s));
                    int sum = 0;
                    for (int i = 0; i <= input1.GetUpperBound(0); i++)
                    {
                        sum = sum + input1[i];
                    }
                    Console.WriteLine("**Result=" + Convert.ToString(sum));
                }
                else if (option == 2)
                {
                    Console.WriteLine();
                    Console.Write("Input integer numbers with \",\" ");
                    string[] input = Console.ReadLine().Split(',');
                    int[] input1 = Array.ConvertAll<string, int>(input, s => int.Parse(s));
                    Array.Sort(input1);
                    int result = 1;
                    int x = 0;
                    bool Y = true;
                    for (int i = 2; i <= input1[0];)
                    {
                        x = 0;
                        if (input1[0] == 1)
                        { break; }

                         Y= true;
                        foreach (int item in input1)
                        {
                            if (item % i != 0)
                            {
                              Y = false;
                            }

                        }
                        if (Y == true)
                        {
                          foreach (int item in input1)
                            {
                              input1[x] = item / i;
                                x =x+1;
                            }
                            result =result * i;
                        }
                        else
                        {
                            result =result+1;
                        }
                    }
                    Console.WriteLine("**Result=" +result);
                }
                else if (option == 3)
                {
                    Console.WriteLine();
                    Console.Write("Input integer numbers with \",\" ");
                    string[] input = Console.ReadLine().Split(',');
                    Array.Sort(input);
                    Array.Reverse(input);
                    Console.Write("**Result=" );
                    foreach (string item in input)
                    Console.Write(item+" ");
                }
            }
            while (option != 4);
        }
    }
}