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Created a new thread : Primes Calculation Optimization || C# Only!


Heres my code and time try making a faster one and ill try to beat it and remember c# only!

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

namespace Primesv1
{
    internal class Program
    {
        static void Main()
        {
            const int limit = 1000000;
            const int repetitions = 100;
            long totalTicks = 0;

            for (int i = 0; i < repetitions; i++)
            {
                Stopwatch sw = new Stopwatch();
                sw.Start();

                int primeCount = CountPrimes(limit);

                sw.Stop();
                totalTicks += sw.ElapsedTicks;

                Console.WriteLine($"Iteration {i + 1}: Found {primeCount} prime numbers in {sw.ElapsedMilliseconds} ms");
            }

            double averageTimeMs = (double)totalTicks / Stopwatch.Frequency / repetitions * 1000;
            Console.WriteLine($"\nAverage time for {repetitions} iterations: {averageTimeMs} ms");
        }

        static int CountPrimes(int n)
        {
            bool[] isPrime = new bool[n + 1];
            for (int i = 2; i <= n; i++)
            {
                isPrime[i] = true;
            }

            for (int p = 2; p * p <= n; p++)
            {
                if (isPrime[p])
                {
                    for (int i = p * p; i <= n; i += p)
                    {
                        isPrime[i] = false;
                    }
                }
            }

            int count = 0;
            for (int i = 2; i <= n; i++)
            {
                if (isPrime[i])
                {
                    count++;
                }
            }

            return count;
        }
    }
}

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