CS 280 Data Structures

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CS 280Data Structures

• Professor John Peterson

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Grading the Projects

• Boo-boos
• Not allowing bubble sort to exit soon enough
• Mistakes in the heapify, especially stage 2
• Mistakes in the random data generator,
  particularly the almost sorted.
• Instance variables that shouldnt be
• Bad variable names / cryptic code
• Not keeping track of numSwaps / compares
• Not deleting useless code from a project
• Casting always an error except (int) to convert
  float to int.
• Copying in illogical places (should be in new
  Snapshot)

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Homework Wrapup

• interface ComparableltTgt
• public boolean gtr(T x, T y)
• class Student
• public int studentNumber
• public String studentName
• Comparable to sort students by number.
• Comparable to sort students by name.
• Sort students given an array of students and a
  Comparable object.
• Write the signature of a general sort method
  using arrays and a comparable

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Generic Methods

• Suppose we dont know what sort of object is
  being sorted but we do know that the sort will
  take an array of these objects and a Comparable
  how would you write the signature of this more
  general sort method? (Warning we havent
  covered some of this so you might have to guess
  part of the answer!)

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Questions on the Practice Quiz
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Complexity Practice