わーい

Program.cs

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

namespace Friends
{
    class Program
    {
        static string[] skill = new string[] {"C#","クソリプ","エアプ","煽り","扇風機であぁぁぁってするやつ","" };

        static void Main(string[] args)
        {
            bool loop = true;
            while (loop)
            {
                Console.WriteLine("1:わーい 2:すごーい 3:たのしー 4:任意文字列 5:らんだむー 6:おわりー");
                var input = Console.ReadLine();
                switch (input)
                {
                    case "1":
                        Wai();
                        break;

                    case "2":
                        Sugoi();
                        break;

                    case "3":
                        Tanoshi();
                        break;

                    case "4":
                        Console.Write("文字列>");
                        Friends(Console.ReadLine());
                        break;

                    case "5":
                        Random();
                        break;

                    case "6":
                        loop = false;
                        break;

                    default:                        
                        break;
                }
                Console.WriteLine();
                Console.WriteLine();
            }
        }

        static void Wai()
        {
            Console.Write("わーい");
        }

        static void Sugoi()
        {
            Console.Write("すごーい");
        }

        static void Tanoshi()
        {
            Console.Write("たのしー");
        }

        static void Friends(string skill)
        {
            Console.WriteLine("君は" + skill + "がとくいなフレンズなんだね！！");
        }

        static void Random()
        {
            System.Random ran = new System.Random();
            int count = ran.Next(10);
            for (int i = 0; i < count; i++)
            {
                switch (ran.Next(4))
                {
                    case 0:
                        Wai();
                        break;

                    case 1:
                        Sugoi();
                        break;

                    case 2:
                        Tanoshi();
                        break;

                    case 3:
                        Friends(skill[ran.Next(5)]);
                        break;
                }
            }
        }
    }
}