CO 442/642 - Fall 2015 - Writing Guidelines
The writing score for assignments will be judged according to adherence to the following guidelines (which may be updated):
(1) Do not use proof by picture or symbolic notation such as , , etc. Words should
suff

CO 442/642 Assignment 2
Due Tuesday October 20
1. Prove that, for non-negative integers k and l, there exists an integer h such that for each graph
G either:
(1) G contains k vertex disjoint cycles each of length at least l, or
(2) there is a set X V (G)

CO 442/642 - GRAPH THEORY
COURSE OUTLINE FOR FALL 2015
1. The Basics
1.1. Time and Place. Lectures are on TR at 1:00-2:20 in EV1 350.
1.2. Instructors. The professor responsible for the course is
Luke Postle: MC 6018; lpostle@uwaterloo.ca
1.3. Text and ot

CO 442/642 Assignment 1
Due Thursday October 1
1. Let G = (V, E) be a simple graph with no K4 -minor.
(a) Prove that, if P is a longest path in G and x is an end of P with degree at least 3, then
there is a circuit C with a chord f such that V (C) V (P )

CO 442/642 GRAPH THEORY
SYLLABUS FALL 2015
The following is an overview of the course and a detailed week-by-week syllabus.
Homeworks are due at the beginning of class on the appropriate Thursday. Please
note that this syllabus is tentative. It may be nec

CO 442/642 Assignment 0
Due Thursday September 17
1. Let n 1 be an integer. Prove that a sequence of positive integers d1 , d2 , . . . , dn is the degree
sequence of a tree if and only if d1 + d2 + . . . + dn = 2n 2.
2. Let S = cfw_x1 , x2 , . . . , xn b