Chapter 8 Recursive Thinking

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Chapter 8Recursive Thinking

• CS 260 Data Structures
• Indiana University Purdue University Fort Wayne

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Recursive thinking

• We will just briefly review the concept of
  recursion
• Recursion . . .
• is the concept of a method calling itself
• is often an alternative to iteration
• sometimes provides a simpler solution
• Recursive algorithms
• A recursive algorithm must have at least one
  stopping case with a non-recursive solution
• Other cases must be replaced by reduced cases
  closer to a stopping case

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Recursion example

• Add up all the integers in a linked list
• Note that the reduced case it closer to the
  stopping case because the length of the linked
  list pointed to by head.link is closer to zero

public static int addUp( IntNode head )
if ( head null ) return 0

// stopping case else
return head.data Node.addUp( head.link )
// reduced case
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