ACSL Computer Challenge

ACSL has divisions tailored to all levels of student computer science expertise.  Most divisions have a take home programming problem but the ACSL classroom division is 10-question test with no programming required. Questions like the questions below can easily become a part of a CS class or club.  There is a complete set of sample questions on the ACSL web site at  The site also includes a link for How ACSL Works as well as FAQ link.

As in the past, ACSL will send, upon registration, a free contest year question CD to all new advisors who are members of CSTA.

Some sample problems are shown below with solutions at the bottom.

1.  Boolean Algebra

     Simplify: ~ (A + B) (A * ~ B + B * ~ C)

2.  Computer Number Systems 

     What is the 10th term expressed in octal of the following sequence 18, 1002, 118, 1016?

3.  LISP 

     Evaluate:   (EXP (DIV (MULT (ADD 2 (SUB 4 2)) 3) 2) 4) 

4.  Prefix/Infix/Postfix

     Evaluate the following postfix expression:  4 3 + 7 5 – * 2 ^

5.  Bit String Flicking

     What bit strings make the following equation true?  (LCIRC-3 (RSHIFT-2 X)) = 10000 

*****************************Solutions:  1. 0  2. 1448  3. 1296  4. 196  5. 010**

Other short answer test topics that expose students to important CS concepts include Recursive Functions, What Does This Program Do?, Digital Electronics, Graph Theory, Data Structures, Assembly Language, and FSAs.  All topics are explained in the contest materials and can be taught in a 45-minute class period.  Students can gain exposure to these.​

Every programming problem for each contest has never been used before and is tailored to the students’ level of ability.  They require creative problem solving in a programming language of each student’s choice.  Students are given sample data and must thoroughly test their solutions.

If you are interested in participating in the ACSL contests, please visit our web site  All questions about ACSL can be sent to Jerry Tebrow at
Register your team today!