Author Archives: Stacey Armstrong

SIGCSE in Dallas – Vol. I

Sign up an attend SIGCE in Dallas, Texas in March of 2011 if you have not already done so.
Dallas is a great city and SIGCSE will be packed with great presentations and discussions for teachers at the high school and university level.    http://www.sigcse.org/sigcse2011/

Need a place to stay?  The Embassy Suites at Market Square is nearby and a great place.
http://embassysuites1.hilton.com/en_US/es/hotel/DALFWES-Embassy-Suites-Dallas-Market-Center-Texas/index.do?brand_id=ES&brand_directory=/en/es/&xch=768816798,YAKFDSX51UQVYCSGBIUM22Q

Need a place to eat?  Babe’s Chicken House if Awesome!  The one in Roanoke is the Best!  If I ever steer you wrong on food, I will pay for your meal!

Check my blog later for more SIGCSE inside information.

CS News – Everyone Needs to Learn to “Crank Code”

Why Johnny Can’t Program

This blog post has been flying around the SIGCSE and AP lists this past week, but I wanted to post a link to it again.  This is a great post and one that we all need to read.
Everyone needs to understand how to write a bit of code.  In order to truly create or innovate, everyone need the basic skill of code writing.  If we are going to remain a nation of innovators, we need to teach kids how to “crank code” as these skills are often used to help cool ideas take root.
My sons are both in elementary school and are learning to write code in Scratch.  They will transition to languages like Python and Java when they are ready, but they are already learning fundamental Computer Science concepts like decision-making, iteration, and list processing that will enable them to create and innovate later.

Java.writeMyCode() – Vol. I – BigInteger

Programming contests are very popular in Texas and most areas of the state host at least 1 each month.  They are great vehicles through which to increase enrollment and to get students excited about “cranking code”.

It is very important to know what tools are available in your language before attending a contest.  If the language being used provides a tool to help solve a problem, then teams should use that tool as part of the solution instead of writing every single line of code from scratch.  I stress to my students to never re-invent the wheel.  If the language already has a perfectly good wheel, put that sucker on your car and hit the road.

Java has lots of cool stuff built-in.  BigInteger is a class that has many methods in it that can make solving certain math related contest problems much easier.  BigInteger contains an isProbablePrime() method.  This is quite useful at contests.

Using BigInteger in Java

Using BigInteger in Java

It is equally important that student understand the algorithm being used to determine if a number is prime and how to create such an algorithm.  Learning the fundamental algorithmic concepts is critical to being a well rounded CS student, but for contest purposes, it is all about speed and accuracy so using built-in methods where possible helps save time and prevent errors.