Unweighted Set-Covering: Difference between revisions

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| [[Alon; Moshkovitz & Safra (Unweighted Set-Covering The Set-Covering Problem)|Alon; Moshkovitz & Safra]] || 2006 || $O(nlogn)$ ||  ||  || Deterministic || [https://dl-acm-org.ezproxy.canberra.edu.au/doi/pdf/10.1145/1150334.1150336 Time]
| [[Alon; Moshkovitz & Safra (Unweighted Set-Covering The Set-Covering Problem)|Alon; Moshkovitz & Safra]] || 2006 || $O(nlogn)$ ||  ||  || Deterministic || [https://dl-acm-org.ezproxy.canberra.edu.au/doi/pdf/10.1145/1150334.1150336 Time]
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| [[Integer linear program Vazirani (Unweighted Set-Covering; Weighted Set-Covering The Set-Covering Problem)|Integer linear program Vazirani]] || 2001 || $O(n^{2})$ || $O(U)$ || \log n || Deterministic || [https://link-springer-com.ezproxy.canberra.edu.au/chapter/10.1007/978-3-662-04565-7_13 Time]
|-
|-
| [[Greedy Algorithm ( The Set-Covering Problem)|Greedy Algorithm]] || 1996 || $O(n^{3} log n)$ || $O(U)$ || \ln(n) - \ln(\ln(n)) + \Theta(1) || Deterministic || [https://dl-acm-org.ezproxy.canberra.edu.au/doi/10.1145/237814.237991 Time]
| [[Greedy Algorithm ( The Set-Covering Problem)|Greedy Algorithm]] || 1996 || $O(n^{3} log n)$ || $O(U)$ || \ln(n) - \ln(\ln(n)) + \Theta(1) || Deterministic || [https://dl-acm-org.ezproxy.canberra.edu.au/doi/10.1145/237814.237991 Time]

Revision as of 13:05, 15 February 2023

Description

Given a universe $U$, i.e. a set of elements $\{1, 2, \ldots, n\}$, and a collection $S$ of $m$ sets whose union is the universe, identify the smallest sub-collection of $S$ whose union is the universe.

Related Problems

Generalizations: Weighted Set-Covering

Parameters

U: the universe of elements to be covered

S: the collection of sets

n: number of elements in the universe

m: number of sets in the collection

H(x): the xth Harmonic number

Table of Algorithms

Name Year Time Space Approximation Factor Model Reference
Alon; Moshkovitz & Safra 2006 $O(nlogn)$ Deterministic Time
Integer linear program Vazirani 2001 $O(n^{2})$ $O(U)$ \log n Deterministic Time
Greedy Algorithm 1996 $O(n^{3} log n)$ $O(U)$ \ln(n) - \ln(\ln(n)) + \Theta(1) Deterministic Time
Lund & Yannakakis 1994 $O({2}^n)$ Exact Deterministic Time
Feige 1998 $O({2}^n)$ Exact Deterministic Time
Raz & Safra 1997 $O(n^{3} log^{3} n)$ Exact Deterministic Time
Dinur & Steurer 2013 $O(n^{2} log n)$ Exact Deterministic Time
Cardoso; Nuno; Abreu; Rui 2014 $O(n^{2})$ Exact Parallel Time
Brute force 1972 $O(U {2}^n)$ $O(U)$ Exact Deterministic