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CS173 Fall 2009 Homework 9
Corrections and Clarifications
November 09, 2009
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1a. There can be 0 toppings on the pizza.

1b. You should use all of the letters.

1c. It's ok for your group to have none of some type of creature,
e.g. you can form a group containing only elves.

1d. Your group must contain exactly one of each type of creature:
one orc, one elf, one goblin.

1e. You should only count the shortest paths (i.e. those of smallest 
length from start to finish).

3. When we mentions S, we mean S_{a,b}.

3a. ***TYPO*** 5 should be 25:
"...to prove that x^2 + y^2 = 25 for any..."

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