Thread — parallel counter

Hard 40 pts New · no attempts yet csharp

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Start two threads incrementing a shared counter (demo with lock).

Static hints

lock object when updating shared counter

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Official solution

using System;
using System.Threading;

class Program {
    static int counter = 0;
    static object gate = new();
    static void Main() {
        var t1 = new Thread(() => { lock (gate) { counter++; } });
        var t2 = new Thread(() => { lock (gate) { counter++; } });
        t1.Start(); t2.Start();
        t1.Join(); t2.Join();
        Console.WriteLine(counter);
    }
}

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Explanation

Race conditions without sync—use lock or Interlocked. Modern code prefers Task/async.

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Thread — parallel counter

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