S3 b

S3 bS3 bS3 bS3 b
S3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 b
S3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 b
S3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 b
S3 bS3 bS3 bS3 bS3 bS3 bS3 bS3 b