Office: | ECS 225e |

Office Hours: | Tuesday & Thursday, 10:30am - 11:30am, or by appointment |

Telephone: | (410) 455-3093 |

E-mail: | chang@umbc.edu |

- (Due 2/6) Problem 0.11, Problem 1.24, Problem 1.42.
- (Due 2/13) Problem 1.23
- (Due 2/20) Exercise 2.6, Problem 2.18
- (Due 2/27) Problem 3.9, Problem 3.10, Problem 3.11
- (Due 3/13) Exercise 5.5, Exercise 5.6, Problem 5.20
- (Due 3/20) Problem 5.10, Problem 5.11 and the following:
- Let L1 = { < M > | L(M) = Sigma* } and L2 = { < M > | L(M) is infinite }.
- Prove that L1 and L2 are reducible to each other under mapping reductions.

- (Due 4/3) Consider the following languages:
- L1 = { < M > | L(M) contains at least 1234 strings }
- L2 = { < M > | L(M) contains exactly 1234 strings }
- L3 = { < M > | there exists a string x such that M accepts x within 1234 steps }

- decidable
- Turing recognizable
- co-Turing recognizable
- neither Turing recognizable nor co-Turing recognizable

- (Due 4/17) Homework 8 is cancelled. Next homework is HW9.
- (Due 4/24) Problem 7.21, Problem 7.30 and Problem 7.34.
- (Due 5/1) Problems 7.29, 7.40 and 8.19
- (Due 5/8) Problems 8.20, 9.19 and 9.21

Last Modified: Tue Apr 15 17:24:37 EDT 1997 Richard Chang, chang@gl.umbc.edu