CMPSCI 601: Theory of Computation

David Mix Barrington

Spring, 2003

Solutions to Practice Exam #1

Posted Thursday 26 March 2003

Actual (in-class) exam is Monday 31 March 2003

Solutions are in blue.

Directions: Each question is a statement that may be true or false. Please state whether it is true or false -- you will get five points for a correct boolean answer and there is no penalty for a wrong guess. Then justify your answer -- the remaining points will depend on the quality and validity of your justification. Problems with higher point values will tend to require longer justifications, but this will not always be the case.

Crib sheet: I will state some useful definitions after the questions -- these will also be available during the in-class exam.

Types of variables: Unless otherwise indicated, a variable A or B denotes a language, D denotes a DFA, G denotes a context-free grammar, M denotes a Turing machine, n denotes a number, and w denotes a string. Remember that N is the set of all numbers, which we may also think of as the set Sigma* of all strings.

Crib Sheet:

Last modified 27 March 2003