CS 365 Homework 2 Answers

17

The arrays "x" and "m" have to be put in separate procedures so that one is active only when the other is not.

24

Example code:

case ThisMonth of
  Sep, Apr, Jun, Nov: days := 30;
  Feb: days := 28;
  Jan, Mar, May, Jul, Aug, Oct, Dec: days := 31;
end;

The last case arm could be handled by an otherwise clause, or all the months could be written as separate cases.

25

Suppose there are N cases. Sequential test takes at least one test, at most N tests, and an average of N/2 tests. A jump table takes constant time. Binary search takes average time proportional to log_2(N). The key parameter is the number of cases.

End of chapter, 15

This is one of many possible ways to write it:

< case statement > ::= case < expression > of
  < case clause > [; < case clause >]*
  [otherwise < statement >] end

It is OK to make the otherwise clause mandatory.

Send mail to Bruce MacLennan / MacLennan@cs.utk.edu