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Thread-Safe Hit Counter — lock
Scenario: Your website counts page hits from multiple threads. Implement a thread-safe increment and read. What to implement: - HitCounter.Increment() - HitCounter.GetValue() Rules: - Must be safe when 20 threads increment 50,000 times each - Use lock (monitor) correctly ✅ Implement ONLY the TODO methods.
✅ Input intentionally includes spaces, quotes, unicode α/β, emoji ✅, and special chars to test parsing + thread-safe processing.
Threads + Thread Safety scenario (students implement ONLY TODO methods)
Ctrl+C
using System; // Console
using System.Collections.Generic; // List
using System.Threading; // Thread
namespace ItTechGenie.M1.Threads.Q1
{
public class HitCounter
{
private readonly object _gate = new object(); // lock object
private int _count = 0; // shared state
// ✅ TODO: Student must implement only this method
public void Increment()
{
// TODO: use lock to increment _count safely
throw new NotImplementedException();
}
// ✅ TODO: Student must implement only this method
public int GetValue()
{
// TODO: return _count safely
throw new NotImplementedException();
}
}
internal class Program
{
static void Main()
{
var counter = new HitCounter(); // shared counter
int threads = 20; // number of threads
int incPerThread = 50000; // increments per thread
var list = new List<Thread>(); // store threads
for (int i = 0; i < threads; i++) // start workers
{
var t = new Thread(() => // create thread
{
for (int j = 0; j < incPerThread; j++) // repeat increments
counter.Increment(); // shared update
});
list.Add(t); // track thread
t.Start(); // run
}
foreach (var t in list) t.Join(); // wait all
Console.WriteLine("Expected: " + (threads * incPerThread));
Console.WriteLine("Actual : " + counter.GetValue());
}
}
}