CS181 Fall 95 Homework 2 Comments

Last modified: October 24, 1995 2 pm (Wk 4 Tuesday)

Statistics

• 45 people turned in hw2, 51 people enrolled
• 100 high, 94 75-percentile, 90 median, 72 25-percentile, 18 low
• 82 average
  
  
• Point Distribution : 10 points for each of the six subparts of #1 and #2
  40 points for #3 (15 basis, 25 induction step).

Comments and Most Common Errors

• Problem 1a Most people give a very compliated DFSA (actually NFSA!).
  Mistakes can be easily checked by the non-acceptance of 0111100.
• Problem 2a Some people include a dead state, which is not in the original diagram.
  Transition tables should represent a machine exactly - no more, no less.
• Problem 2d Most incorrect regular expressions (R.E.s) can be tested with the string 001 (which should be accepted).
• Problem 3 Some students just copied a similar proof in the book, failing to realize that the proff in the book was only for DFSAs! 20 points were deducted.