Author: Leon Tabak

Leon Tabak is a professor and chairman of the Department of Computer Science at Cornell College in Mount Vernon, Iowa. He is a senior member of the Institute of Electrical and Electronics Engineers (IEEE). For more than 20 years, he has supported the College Board's Advanced Placement (AP) program by reading examinations, leading workshops for AP teachers, and reviewing syllabi that teachers include as part of their applications to teach AP courses. Professor Tabak earned his degrees at the Massachusetts Institute of Technology, Boston, University, and Worcester Polytechnic Institute.

Our Elevator Speech

Our students often hear advice about how to find opportunities. “You never know whom might meet and who might be able to help you,” teachers and parents and people in the college’s career office tell them. “Be ready to explain your ambitions clearly and concisely.” Those of us who teach and study computer science might…

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For which problems do algorithms that generate a solution exist? This question defines the study of computability. A programmer can direct a computer to repeat a series of arithmetic operations until some logical condition is satisfied. If the programmer fails to specify the terminating condition correctly, the computer will continue executing the instructions forever. Will…

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For computer scientists, the word complexity denotes the amount of work required to solve a problem using a given algorithm. An algorithm is the sequence of arithmetic and logical operations that lead to the solution of a problem. Computer scientists measure the complexity of an algorithm by comparing the number of instructions that a computer…

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