CS 280 Data Structures

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CS 280Data Structures

• Professor John Peterson

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Statics

• Understanding how and when to use statics is a
  really tough part of Java.
• What situations does it make sense in to use
  static variables? Static final variables? A
  class with only static methods?
• What is special about static vars/methods?
• What are the rules of a static method?
• Lets look at how to store sort functions into
  statics.

3
heapify

• void heapify(int i, Sortable s, int n) // n is
  the limit of s
• int l left(i) // 2i1
• int r right(i) // 2i2
• if (r lt n)
• if (s.gtr(l, i) s.gtr(r, i))
• if (s.gtr(l,r))
• s.swap(i,l)
• heapify(l,s,n)
• else
• s.swap(i,r)
• heapify(r,s,n) //
  Missing in old slide
• else if (l lt n)
• if (s.gtr(l,i)) swap(i,l) //
  Bug in old slide