Consider two new operations in addition to the usual read (R) and
write (W) for transactions: Fuzz(F) and Defuzz (D). These are
implemented atomically by the database system, similar to the read and
write operations. Based upon the application semantics, the following
compatibility matrix is defined (other details of fuzz and defuzz are
unimportant):

	Read	Write	Fuzz	DeFuzz
Read	Y	N	Y	Y
Write	N	N	N	N
Fuzz	Y	N	N	Y
Defuzz	Y	N	Y	N
 Based upon the above compatibility matrix, is the following execution
conflict serializable? Draw its Serialization Graph.
R1[x] W2[x] W3[x] R4[y] F2[y] F3[y] F4[z] F4[y] D1[y] R3[z] C1 C2 C3