 
Summary: 9/22/2010
1
Computational problems algorithmsComputational problems, algorithms,
runtime, hardness
(a brief introduction to theoretical computer science)
slides by Vincent Conitzer
Set Cover (a computational problem)
· We are given:
A finite set S = {1, ..., n}
A collection of subsets of S: S1, S2, ..., Sm
· We are asked:
Find a subset T of {1, ..., m} such that Uj in TSj= S
Minimize TMinimize T
· Decision variant of the problem:
we are additionally given a target size k, and
asked whether a T of size at most k will suffice
Set Cover (a computational problem)
· One instance of the set cover problem:
S = {1,2,3,4,5,6},
S1 = {1,2,4},
