THREAD_THREADPOOL/task.cs - master - giges/ParallelComputingSystems

THREAD_THREADPOOL/task.cs
218 строк6 KB
RukavishnikovNA
zadachi
19 дек 2025, 10:33
19 дек 2025, 10:33b51dbc6
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;

public static class ParallelHomework
{
    
    public static void Main(string[] args)
    {
        ParallelHomework.ThreadMultiArrProcess();
        ParallelHomework.ThreadPoolSumProcess();
        ParallelHomework.ThreadMaxArrProcess();
        ParallelHomework.ThreadPoolFilterMoreThenFiveProcess();

        Console.ReadLine();
    }
    
    // 1) Умножение массива через Thread
    public static void ThreadMultiArrProcess()
    {
        int[] numbers = { 1,2,3,4,5,6,7,8,9,10 };

        int mid = numbers.Length / 2;

        Thread t1 = new Thread(() =>
        {
            Console.WriteLine($"Поток {Thread.CurrentThread.ManagedThreadId}");
            ProcessArrayMulti(numbers, 0, mid);
        });

        Thread t2 = new Thread(() =>
        {
            Console.WriteLine($"Поток {Thread.CurrentThread.ManagedThreadId}");
            ProcessArrayMulti(numbers, mid, numbers.Length);
        });

        t1.Start();
        t2.Start();

        // Дожидаемся завершения потоков (Thread.Join)
        t1.Join();
        t2.Join();

        Console.WriteLine("Result: " + string.Join(", ", numbers));
    }

    // endIndex — НЕ включительно: [startIndex, endIndex)
    public static void ProcessArrayMulti(int[] array, int startIndex, int endIndex)
    {
        for (int i = startIndex; i < endIndex; i++)
            array[i] *= 2;
    }

    // 2) Суммирование через ThreadPool
    public static void ThreadPoolSumProcess()
    {
        int[] numbers = { 1,2,3,4,5,6,7,8,9,10 };

        int workers = 2;
        int chunk = (int)Math.Ceiling(numbers.Length / (double)workers);

        int[] partial = new int[workers];
        AutoResetEvent[] done = new AutoResetEvent[workers];

        for (int w = 0; w < workers; w++)
        {
            done[w] = new AutoResetEvent(false);

            int start = w * chunk;
            int end = Math.Min(numbers.Length, start + chunk);

            var state = new SumState
            {
                Array = numbers,
                Start = start,
                End = end,
                PartialSums = partial,
                Index = w,
                Done = done[w]
            };

            ThreadPool.QueueUserWorkItem(SumWorker, state);
        }

        // Ждём завершения всех work item (WaitHandle.WaitAll + AutoResetEvent)
        WaitHandle.WaitAll(done);

        int sum = partial.Sum();
        Console.WriteLine($"Sum = {sum}");
    }

    private static void SumWorker(object? obj)
    {
        Console.WriteLine($"Поток {Thread.CurrentThread.ManagedThreadId}");

        var s = (SumState)obj!;
        int local = 0;

        for (int i = s.Start; i < s.End; i++)
            local += s.Array[i];

        s.PartialSums[s.Index] = local;
        s.Done.Set();
    }

    private sealed class SumState
    {
        public int[] Array = null!;
        public int Start;
        public int End;
        public int[] PartialSums = null!;
        public int Index;
        public AutoResetEvent Done = null!;
    }

    // 3) Поиск максимума через Thread
    public static void ThreadMaxArrProcess()
    {
        int[] numbers = { 3, 17, 5, 22, 9, 11, 8, 30, 15 };

        int mid = numbers.Length / 2;
        int[] partialMax = new int[2];

        Thread t1 = new Thread(() =>
        {
            Console.WriteLine($"Поток {Thread.CurrentThread.ManagedThreadId}");
            partialMax[0] = MaxRange(numbers, 0, mid);
        });

        Thread t2 = new Thread(() =>
        {
            Console.WriteLine($"Поток {Thread.CurrentThread.ManagedThreadId}");
            partialMax[1] = MaxRange(numbers, mid, numbers.Length);
        });

        t1.Start();
        t2.Start();
        t1.Join();
        t2.Join();

        int max = Math.Max(partialMax[0], partialMax[1]);
        Console.WriteLine($"Max = {max}");
    }

    private static int MaxRange(int[] array, int startIndex, int endIndex)
    {
        int max = int.MinValue;
        for (int i = startIndex; i < endIndex; i++)
            if (array[i] > max) max = array[i];
        return max;
    }

    // 4) Фильтрация > 5 через ThreadPool
    public static void ThreadPoolFilterMoreThenFiveProcess()
    {
        int[] numbers = { 1, 8, 3, 10, 5, 6, 2, 9, 7, 4 };

        List<int> filteredNumbers = new List<int>();
        object locker = new object();

        int workers = 2;
        int chunk = (int)Math.Ceiling(numbers.Length / (double)workers);

        AutoResetEvent[] done = new AutoResetEvent[workers];

        for (int w = 0; w < workers; w++)
        {
            done[w] = new AutoResetEvent(false);

            int start = w * chunk;
            int end = Math.Min(numbers.Length, start + chunk);

            var state = new FilterState
            {
                Array = numbers,
                Start = start,
                End = end,
                Result = filteredNumbers,
                Locker = locker,
                Done = done[w]
            };

            ThreadPool.QueueUserWorkItem(FilterWorker, state);
        }

        WaitHandle.WaitAll(done);

        Console.WriteLine("Filtered (>5): " + string.Join(", ", filteredNumbers));
    }

    private static void FilterWorker(object? obj)
    {
        Console.WriteLine($"Поток {Thread.CurrentThread.ManagedThreadId}");

        var s = (FilterState)obj!;
        List<int> local = new List<int>();

        for (int i = s.Start; i < s.End; i++)
            if (s.Array[i] > 5) local.Add(s.Array[i]);

        // Потокобезопасное добавление в общий List через lock (Monitor)
        lock (s.Locker)
            s.Result.AddRange(local);

        s.Done.Set();
    }

    private sealed class FilterState
    {
        public int[] Array = null!;
        public int Start;
        public int End;
        public List<int> Result = null!;
        public object Locker = null!;
        public AutoResetEvent Done = null!;
    }
}