C SC 205 Lecture 6: Recursion, Part 1
major resources: Data Structures and the Java Collections Framework Second Edition, William Collins, McGraw-Hill, 2005
Introduction to Programming and OO Design using Java, Niño and Hosch, Wiley & Sons, 2002

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Wednesday September 26 (week 3)

preliminary: review of parameter passing

• Java uses pass by value, period. Value passed to method may be primitive value or object reference.
• object whose reference is argument can be modified by callee (note: making reference final does not prevent)
• similarity of parameter passing and assignment w.r.t. type compatibility (subclass substitution)

Towers of Hanoi Demonstration and Analysis

• analyzing Towers of Hanoi through demonstration
• Sequence of moves to solve 1-disk problem
• Sequence of moves to solve 2-disk problem
• Sequence of moves to solve 3-disk problem
• Preduct sequence of moves to solve 4-disk problem
• Predict how many moves needed to solve 4-disk problem
• Predict how many moves needed to solve N-disk problem (Big O)
• notice pattern of moves and their self-similarity
• self-similarity is characteristic of problem with naturally recursive solution