//Първа задача

using System;
using System.Threading;

namespace ThreadsPractice1
{
    class Program
    {
        static void Main(string[] args)
        {
            int size = 20;
            int[] arr = new int[size];

            int first = 0;
            int second = size - 1;

            Random rnd = new Random();

            Thread A = new Thread(() =>
            {
                while (true)
                {
                    if (first < size / 2)
                    {
                        arr[first] = rnd.Next(1, 51);
                        first++;
                    }
                    else
                    {
                        break;
                    }
                    Thread.Sleep(500);
                }
            });

            Thread B = new Thread(() =>
            {
                while (true)
                {
                    if (second >= size / 2)
                    {
                        arr[second] = rnd.Next(51, 101);
                        second--;
                    }
                    else
                    {
                        break;
                    }
                    Thread.Sleep(500);
                }
            });

            A.Start();
            B.Start();

            A.Join();
            B.Join();

            for (int i = 0; i < arr.Length; i++)
            {
                Console.Write("|" + arr[i]);
            }
            Console.WriteLine("|");
        }
    }
}

//Втора задача

using System;
using System.Threading;

namespace ThreadPractice2
{
    internal class Program
    {
        static void Main(string[] args)
        {
            int size = 50;
            char[] arr = new char[50];
            string str = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
            Random rnd = new Random();

            for (int i = 0; i < size; i++)
            {
                arr[i] = str[rnd.Next(str.Length)];
            }

            int letterCount = 0;
            Thread A = new Thread(() =>
            {
                foreach(char i in arr)
                {
                    if (char.IsLetter(i))
                    {
                        letterCount++;
                    }
                }
            });

            int numberCount = 0;
            Thread B = new Thread(() =>
            {
                foreach (char i in arr)
                {
                    if (char.IsNumber(i))
                    {
                        numberCount++;
                    }
                }
            });

            A.Start();
            B.Start();

            A.Join();
            B.Join();

            Console.WriteLine($"Number of letters: {letterCount}");
            Console.WriteLine($"Number of numbers: {numberCount}");
        }
    }
}