class FastComparer : IEqualityComparer<Object>
    {
        bool IEqualityComparer<object>.Equals(object x, object y)
        {
            return ReferenceEquals(x, y);
        }

        int IEqualityComparer<object>.GetHashCode(object obj)
        {
            return obj.GetHashCode();
        }
    }

    public class ObjectIDGeneratorXPlatform
    {
        private Dictionary<object, long> mObjects;
        private long mCounter = 1;

        public ObjectIDGeneratorXPlatform()
        {
            mObjects = new Dictionary<object, long>(4096, new FastComparer());
        }

        public long GetId(Object obj, out bool firstTime)
        {
            long id;
            if (mObjects.TryGetValue(obj, out id))
            {
                firstTime = false;
                return id;
            }
            else
            {
                firstTime = true;
                id = mCounter;
                ++mCounter;
                mObjects.Add(obj, id);
                return id;
            }
        }
    }