Recitation files.

SES #	Topics	RECITATION NOTES
R1	Specification and testing	(PDF)
R2	ADT, rep exposure, and object model diagrams	(PDF)
R3	Abstraction functions and representation invariants	(PDF)
R4	Equality and hashing	(PDF)
R5	True subtyping and the substitution principle	(PDF)
R6	Design patterns	(PDF)