CSC 148H: INTRODUCTION TO COMPUTER SCIENCE

Old Announcements -- Week 1

12 September: Handbook

The Course Handbook is now available at the bookstore, along with the lecture slides. Because of the delay, the bookstore has reduced the price for the Handbook from $18 to $15.

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11 September: Old editions

Question: Can we use editions of the Lectures Notes or Course Handbook from before fall 96?
Answer: The fall 96 editions are significantly different from earlier ones.
Handbook: In older editions, the sample assignments are not written in OOT. There are also many other updates this year. You may use an old edition, but it is your responsibility to read and be familiar with the rules stated in the front section (pages 1-22) of the fall 1996 edition. These rules apply to you.
Lecture Notes: Almost every section of the notes is significantly different in the new edition. You do not have to own these notes, but if you do, I think it would be frustrating to work with an old edition.

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11 September: Assnt 0 -- terminology

Students have asked for explanation of some terminology:

• Is 0 considered divisible by 11?.
  11 goes into 0 evenly: it goes in 0 times, with no remainder. So yes, 0 it divisible by 11.
  However, 0 is not a positive integer, so your program does not have to handle it.
• 50 decimal digits long.
  "Decimal" here means simply "base 10". It is not meant to imply that there is a decimal point or fractional part to the integer.
• most significant digit.
  The most significant digit is the leftmost digit.
• deleting the units digit.
  The units digit (also called the "ones" digit) is the rightmost digit.

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11 September: Bookstore update

The csc148 Lecture Notes are now available in the bookstore. The price is $10.
The csc148 Handbook is expected to be available in the next day or so. It's price will be $18.

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11 September: Assnt 0 -- leading zeros

Question: The A0 handout says that students shouldn't worry about a BigInt having leading zeros. Why does the starter code contain a procedure (that students are to fill in) to strip a leading zero?
Answer: Each number to be checked will not contain leading zeros when it is read in. However, the process of subtracting deleted units digits can create a leading zero. (Play around with some examples so that you can see how this happens.) This violates the "preconditions" of procedure SubtractLastDigit, and so any leading zero must be removed before SubtractLastDigit is called again.

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9 September: PC account names

Both the Course Handbook and the published lecture slides say that computer accounts for the course begin with "a148". This is incorrect; they actually begin with "f148" to indicate that this is a fall course.