OFFICE: Math 612 PHONE: (765) 494-1975 EMAIL: eremenko@math.purdue.edu
MIDTERM EXAMS schedule:
1. Sept. 19, in class,
2. Oct. 24, 7 p.m. GRISS 180
HW 3: p. 266, 8, 9, 21, 23, 31, 32, 33, 34 (due on Tuesday, Sep. 10, before the class begins).
HW 4: p. 294: 13, 15, 17, 20, 31, 51, 52,
p. 316: 5(abcd), 8, 18, 40, 43, 44, 45
(due on Tuesday, Sep. 17, before the class starts).
HW 5: p. 329: 3df, 24, 28, 35, 36 (due Tuesday, Sep. 24, before the class starts).
HW 6: p. 331: 37, 45, p. 359: 3, 5, 9, 10, 13, 14, 25, p. 367: 3, 6.
HW 7: p. 367: 8, 10, 12, 16, p. 199: 1, 3, 5, 6, 8, 10, 14, 18. (due October 15).
HW 8: p. 248: 3, 8, 9, 18, 19, 22, 25, 26, 30,
HW 9: p. 444:11; p. 454: 5,6,12,13,16,17,18,19,21,23.
HW10: p. 463: 3, 7, 9, 11, 28, 29, 32, 35, 38, 41, 42, p. 473: 1,6,7. (due Nov. 12).
HW 12: p. 485: 1, 2, 5, 7, 19, 20, 47, 48, 69, p. 508: 5, 7, 21. (due December 3).
I was asked for a reference on Havel-Hakimi. Here it is: Douglas West, "Introduction to Graph Theory"
CANCELLATION OF CLASS : Tuesday, November 26 (YES!)
FINAL EXAM: as scheduled by Purdue: Dec. 12
PROBLEM (just for fun): Five married couples gathered for a party.
One of the participants, a sociologist, decided to make a little
research: he asks everybody how many handshakes s/he made during the party.
He asks 9 people (all except himself)
and gets to his surprise all possible
answers, namely 0,1,2,3,4,5,6,7,8.
How many handshakes made the wife of the sociologist?
(Nobody shakes hands with himself/herself, nobody shakes hands with
his/her spouse, and each pair shakes hands at most once).
This problem was given to a friend of mine, a computer scientist, in a job interview with a software company:-) She got the job!
ANOTHER ONE (also from a job interview with a friend, a computer scientist, in Israel) Suppose we have a 100-floor building and glass balls with the following property. There exist an integer n between 1 and 100 such that if a ball is dropped from n-th or higher floor, the ball breaks, while if dropped from (n-1)st or lower floor, it does not. You want to find this number n using two balls. What is the optimal algorithm to do this? (We minimize the number of drops. For every algorithm, there is a worst case, the building which requires maximal number of drops for this algorithm. You want to find an algorithm which minimizes this maximal number. For example, if you have only one ball, there is a simple algorithm which would require 99 drops in the worst case).