Nullability of reference types in type of parameter 'X' of 'int VQCluster.Compare(VQCluster X, VQCluster Y)' doesn't match implicitly implemented member 'int IComparer<VQCluster>.Compare(VQCluster? x, VQCluster? y)' (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'Y' of 'int VQCluster.Compare(VQCluster X, VQCluster Y)' doesn't match implicitly implemented member 'int IComparer<VQCluster>.Compare(VQCluster? x, VQCluster? y)' (possibly because of nullability attributes).

Non-nullable field 'vqClusters' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the field as nullable.

Non-nullable field 'codebook' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the field as nullable.

Non-nullable field 'arrList' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the field as nullable.

Possible null reference return.

Possible null reference argument for parameter 'value' in 'void BinaryWriter.Write(string value)'.

Dereference of a possibly null reference.

Dereference of a possibly null reference.