Why Does My Random Number Generator Only Produce One Unique Number?

Troubleshooting a Random Number Generator Producing Repeated Numbers

Your random number generator (RNG) appears to be generating only a single unique number despite using a loop. Debugging reveals different numbers during loop execution, but upon completion, all array elements hold the same value.

The problem stems from creating a new Random instance within each loop iteration. Since Random is often seeded using the system clock, a rapidly executed loop may repeatedly initialize the Random object with the same seed, leading to identical outputs.

The Solution: A Single, Shared Instance

The fix involves using a single, static Random instance across all calls. This ensures consistent state updates and prevents repeated seed values. To handle multi-threaded scenarios safely, a lock is employed to synchronize access.

Here's the corrected RandomNumber function:

private static readonly Random random = new Random();
private static readonly object syncLock = new object();

public static int RandomNumber(int min, int max)
{
    lock (syncLock) { // Thread-safe access
        return random.Next(min, max);
    }
}

By using a single random instance and synchronizing access with lock, the RNG will maintain its internal state, producing unique random numbers on each call within the loop.

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