CSci 3501 Algorithms and Computability - Lab 7.

October 6. Due Wednesday, October 12 at 11:59pm

What to submit and when:

• All submissions are electronic: by e-mail to elenam at morris.umn.edu and CC to all lab partners. Please do not delete your e-mail from "Sent mail" or your mailbox until the end of the semester.
• When working on the lab, please comment your work so that it is clear what contributions of each person are.
• At the end of the lab each group should send me the results of their in-class work. Please indicate if this is your final submission.
• If your submission at the end of the lab time was not final, please send me(CC to the lab partner(s)) a final copy before the due time. Please use the subject "3501 Lab N", where N is the lab number.

Lab assignment

Work in pairs

Lab overview and goals

The goal of part I of the lab is to practice with JFLAP (a tool for experimenting with finite automata and other computability topics) and to design and test DFAs.

Using JFLAP and naming your files

• Please save your automata files as .jff files and your data as .txt files. Files names must be as follows: names of those in the group followed by question name, e.g. SmithAdams3.jff (where 3 refers to the question number). This will help me in running test data
• To load test data from a file, go to Input -> Multiple Runs -> Load Inputs
• When adding multiple transitions between the same two states, add them one by one. Typing "0, 1" in a label for an arrow will give you a wrong result since the automaton will try to match this input exactly, including the comma.
• When writing DFA, check that every state has a transition on every symbol. JFLAP does not check it.
• Use Convert -> Combine Automata to copy one automaton into a file for another one.
• Do not use "convert to DFA" or "minimize DFA" options.
• Consult the JFLAP tutorial as needed.

Lab tasks

(20 points)

Unless specified otherwise, the alphabet is the set of 0 and 1. Recall that zero is an even number.

Design and test the following finite automata:

1. DFA to recognize the language of all strings that have at most three zeros.
2. DFA to recognize the language of all strings that have an even number of zeros and an odd number of ones.
3. DFA to recognize the language of all strings that end at an even number of zeros (i.e. the longest substring of 0s at the end of the string is of even length).
4. DFA to recognize the language of all strings that have a pattern 01 but not 101
5. DFA to recognize the language of all strings that have an odd number of occurrences of a pattern 01, possibly interleaved with more 1s and 0s. For example, 00011 should be accepted while 010010 should not be.

CSci 3501 course web site.