Status check

• Our last class
• Quiz 13 posted
• A12

ICS211 Course Catalog Description

Algorithms and their complexity, introduction to software engineering, data structures, searching and sorting algorithms, numerical errors.

Oops: Numerical errors

• Didn't cover this explicitly
• 2 parts:
  • Finite precision of represented numbers (includes round-off errors)

      System.out.println(3 / 2);    // 1, due to int math
      System.out.println(2.0 / 3);  // 0.66666... but only so many 6s
      System.out.println(0.1 * 0.1); // 0.010000000000000002
      //due to binary representation limits: 0b110011001100... x 2e-4
    

  • overflow and underflow

      byte b = 127;
      b++;
      System.out.println(b);  // -128 (overflow)
      b--;
      System.out.println(b);  // 127 (underflow)
    

• Boils down to: finite representations used to represent infinite precision/range

From Syllabus: Course Objectives

Upon successfully completing this course, students will be:

• competent Java programmers
• proficient with common best practices in object-oriented programming, software design, and implementation
• familiar with common abstract data types (such as stacks, queues, lists, and trees)
• familiar with common searching and sorting algorithms
• able to evaluate, choose, customize, and implement the most appropriate algorithm or data structure for a given problem

Java Programming

• Did lots of this
• Started with review of basics: conditionals, loops, methods, objects
• Resources: API, Java Tutorial. (Google, StackOverflow, etc often help too.)
• Tools: java, javac, jar, javadoc; IDE; unix
• Java Collections (java.util)
• GUIs (Swing)
• enums, StringBuffer, I/O, binary ops, etc.

Software Engineering and OOP

• Methodology (across models): requirements, design, implement, test (verify/validate), maintain
• OOP principles: abstraction, encapsulation, modularity, reuse, (immutability)
• OOP practicalities: classes, interfaces, inheritance, overriding, polymorphism

Data structures and ADTS

From last time:

• Data structures: array, linked list of nodes
  • circular queue, heap, hash table
  • trees (binary, BST, Huffman)
  • graph (adjacency matrix, adjacency list)
• ADTs: stack, queue, list, (sorted list), priority queue, deque, set, map, graph

Algorithms

• What an algorithm is
  • unambiguous sequence of steps that solves a particular problem in finite time
• Recursion and backtracking
• Algorithm analysis - worst-case growth rate (big-O)
  • implementation evaluation - benchmarking
• Some particular algorithms
  • searching (linear, binary; with trees: DFS, BFS)
  • sorting (six variants)

Practical application

• As per our first online discussion: many factors to consider when selecting algorithm
• Analysis: big-O, especially in different contexts (algorithms and data structurs)
• Assignment practice (choosing design/implementation)

After this course

If you have a B or better:

• ICS311 - Algorithms
• ICS212 - Program Structure (C/C++)

If you have a B- or lower:

• ICS211

Final Exam

• Comprehensive
• ~25% on the hashing, maps, sets, etc.
• About a page or two longer than the others, but same # of points
• Will likely boost your grade (though not a lot)
• Also need an exam average of 70+% to get a B or better.
  • So could have a 90% course average and still only get a B-
• If you're sure the final won't help you enough to bother, you can skip it

Review

Questions?

Final Days

• Branden (LA) wrote a automated practice exam tool you can use to review (link on main page)
• If haven't yet: eCafe feedback (please)
• Finish A12 (grader up Thursday night) and Quiz 13
• Hopefully we'll have all the grades except for final posted by next Wed afternoon

Thank You

• It's been a great first class!
• I'll see you around campus next semester
• And (those of you that come) at the final