using System.Threading;

public class AtomicReference <T> where T : class {
	private T value;
	private bool isSet = false;

	public AtomicReference() { }

	public AtomicReference(T value) {
		this.value = value;
	}

	public T CompareAndSet(T newValue) {
		// change to compere exchange.
		isSet = true;
		return Interlocked.CompareExchange(ref value, value, newValue);
	}

	public bool OptimicSet(T oldvalue) {
		T old;
		do {
			old = value;
		} while (old != CompareAndSet (value));
		return isSet;
	}

	public T Get() {
		return value;
	}
}