Yea.Compression.BitArrayCompress.CountZeros C# (CSharp) Method

        public long CountZeros()
        {
            if (_usingIndexes)
            {
                long ones = _offsets.Count;
                _offsets.Sort();
                long l = _offsets[_offsets.Count - 1];
                return l - ones;
            }

            CheckBitArray();
            int count = _uncompressed.Length << 5;
            long cc = CountOnes();

            return count - cc;
        }