CISC 280 review sheet for first midterm exam

Midterm date: Tuesday, March 12, 2002.

Exam covers Chapter 1. Excluded is the last portion (page 16) of section 1.1.5 labeled "applicative order versus normal order." The only thing you are required to know about RSA encryption is that encryption/decryption needs an efficient expmod function and that key creation needs an efficient primality test function, i.e. fast-prime?.

sample question types

A problem similar to exercise 1.1, i.e. "Evaluate this, this, and this expression."
Evaluate calls to functions which are defined in the question. For example, there are three definitions of a function named f on page 64. Be sure you can reason your way through the steps of the evaluation process on (f 0 0), (f 0 1), (f 1 0), and (f 1 1) for each of the 3 forms of definition.
Problems meant to show you know the special forms. For example, you find that a certain implementation of Scheme is lacking "cond". Redefine the following procedure using "if".
```
(define (foobar x y)
   (cond ((= x y) 12)
	 ((< x y) (- y x))
	 (else (square x)) ))
```
true/false or short answer questions about programming concepts we've covered such as
the distinction between an iteration (or tail recursion) and a linear recursion that is not an iteration.
the order of growth of the two ways of doing exponentiation, of gcd, of fast or slow primality predicate, prime?.
procedures as parameters and as returned values
Problems about writing procedures in scheme:
(a) writing procedures which are possible directly from memory (i.e. have been defined in the book or in class, or have been homework. For example, define sqrt, factorial, fib, expt, fast-expt, gcd, sum, length, the functions about the digits of a number. Note it is not expected that you will rote memorize these, rather that you will remember the specifications and the methods enough to be able to recreate procedures to compute them, if asked.
(b) writing specified procedures which are only similar to ones we've done. For example, define a procedure to compute the odd part of a positive integer. Every integer can be written as a power of 2 times an odd number. This procedure returns the odd number. For example,
(odd-part 5) --> 5, because 5 = (2^0)*5,
(odd-part 20) --> 5, because 20 = (2^2)*5,
(odd-part 48) --> 3, because 48 = (2^4)*3,
It is also a good idea to work exercises from SICP which have not been assigned. Many of these are similar to homework or examples we have done and thus are fair game for the exam.

CISC 280 review sheet for first midterm exam

Midterm date: Tuesday, March 12, 2002.

sample question types

saunders@cis.udel.edu