CS139 – Algorithm Development

Aug 23, 2004

WELCOME!

In Class Exercise

Take out a clean blank 8 ½ by 11 inch piece of paper.

In the top right hand corner of the paper, write your name and your section (lab meets at 9:30 – 1, 11:00 – 2, 12:30 - 3).

On the paper, write the following numbers.

12 17 20 18

Now, average the four numbers

Result should be 16.75

Let’s do a second one.

Write down the following numbers:

13 15 20

Now average the three numbers.

The result should be 16.

Next, work with a group

Get into groups of 3 or 4 people.Put your group member’s names below

your name on the page.The person with the last name closer to

the end of the alphabet will be the recorder for this exercise. All answers will go on her/his paper.

Final Exercise

Write down, in detail, the steps that you went through to compute the averages.

Note that in one case we had 4 numbers, in the other 3. Make sure that your steps include the possibility for n numbers where n is the count of the numbers to average.

You should have no more than 3 or 4 steps.

What did you come up with?

Have the person whose first name is closest to the letter “M” (blank follows) be the reporter for this exercise.

Have the reporter write the directions for your group up on the whiteboard.

What did we just build?

Algorithm – An unambiguous (and precise) set of steps for solving a problem (or sub-problem) in a finite amount of time using a finite amount of data. (Dale and Lewis definition).

Algorithm – A step by step process for solving a problem. (Lewis and Loftus definition).

This course is all about algorithms

We will learn how to think in terms of step by step solutions and implement those solutions on the computer.

We will use the Java programming language for implementation of the algorithms.

Let’s look at the syllabus.