Integer programming: Difference between revisions

Revision as of 20:14, 19 October 2023

Revision as of 04:16, 25 October 2023

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* The original algorithm of Lenstra<ref name=":0" /> had run-time <math>2^{O(n^3)}\cdot (m\cdot \log V)^{O(1)}</math>.

* Kannan<ref>{{Cite journal|last=Kannan|first=Ravi|date=1987-08-01|title=Minkowski's Convex Body Theorem and Integer Programming|url=https://pubsonline.informs.org/doi/abs/10.1287/moor.12.3.415|journal=Mathematics of Operations Research|volume=12|issue=3|pages=415–440|doi=10.1287/moor.12.3.415|s2cid=495512 |issn=0364-765X}}</ref> presented an improved algorithm with run-time <math>n^{O(n)}\cdot (m\cdot \log V)^{O(1)}</math>.<ref>{{Cite journal|last1=Goemans|first1=Michel X.|author1link = Michel Goemans|last2=Rothvoss|first2=Thomas|date=2020-11-07|title=Polynomiality for Bin Packing with a Constant Number of Item Types|journal=[[Journal of the ACM]]|volume=67|issue=6|pages=38:1–38:21|doi=10.1145/3421750|hdl=1721.1/92865 |s2cid=227154747 |issn=0004-5411|doi-access=free}}</ref>

* Frank and Tardos<ref>{{Cite journal|last1=Frank|first1=András|last2=Tardos|first2=Éva|date=1987-03-01|title=An application of simultaneous diophantine approximation in combinatorial optimization|url=https://doi.org/10.1007/BF02579200|journal=Combinatorica|language=en|volume=7|issue=1|pages=49–65|doi=10.1007/BF02579200|s2cid=45585308|issn=1439-6912}}</ref> presented an improved algorithm with run-time <math>n^{2.5 n} \cdot 2^{O(n)} \cdot (m\cdot \log V)^{O(1)}</math>.<ref>{{Cite journal|last1=Bliem|first1=Bernhard|last2=Bredereck|first2=Robert|last3=Niedermeier|first3=Rolf|author3-link=Rolf Niedermeier|date=2016-07-09|title=Complexity of efficient and envy-free resource allocation: few agents, resources, or utility levels|url=https://dl.acm.org/doi/abs/10.5555/3060621.3060636|journal=Proceedings of the Twenty-Fifth [[International Joint Conference on Artificial Intelligence]]|series=IJCAI'16|___location=New York, New York, USA|publisher=AAAI Press|pages=102–108|isbn=978-1-57735-770-4}}</ref><ref>{{Cite book|last1=Bredereck|first1=Robert|last2=Kaczmarczyk|first2=Andrzej|last3=Knop|first3=Dušan|last4=Niedermeier|first4=Rolf|title=Proceedings of the 2019 ACM Conference on Economics and Computation |chapter=High-Multiplicity Fair Allocation: Lenstra Empowered by N-fold Integer Programming |date=2019-06-17|chapter-url=https://doi.org/10.1145/3328526.3329649|series=EC '19|___location=Phoenix, AZ, USA|publisher=Association for Computing Machinery|pages=505–523|doi=10.1145/3328526.3329649|isbn=978-1-4503-6792-9|s2cid=195298520}}</ref>{{Rp|Prop.8}}

* Dadush<ref>Dadush, Daniel (2012-06-14). [https://homepages.cwi.nl/~dadush/papers/dadush-thesis.pdf "Integer Programming, Lattice Algorithms, and Deterministic Volume Estimation].</ref> presented an improved algorithm with run-time <math>n^n \cdot 2^{O(n)} \cdot (m \cdot \log V)^{O(1)}</math>.

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===Heuristic methods===

Since integer linear programming is [[NP-hard]], many problem instances are intractable and so heuristic methods must be used instead. For example, [[tabu search]] can be used to search for solutions to ILPs.<ref>{{cite journal|last=Glover|first=F.|author-link=Fred W. Glover|title=Tabu search-Part II|journal=ORSA Journal on Computing|year=1989|volume=1|issue=3|pages=4–32|doi= 10.1287/ijoc.2.1.4 |s2cid=207225435|url=https://semanticscholar.org/paper/9a3203a26112ec33d34233ba8b38e5509490f2a0}}</ref> To use tabu search to solve ILPs, moves can be defined as incrementing or decrementing an integer constrained variable of a feasible solution while keeping all other integer-constrained variables constant. The unrestricted variables are then solved for. Short-term memory can consist of previously tried solutions while medium-term memory can consist of values for the integer constrained variables that have resulted in high objective values (assuming the ILP is a maximization problem). Finally, long-term memory can guide the search towards integer values that have not previously been tried.

Other heuristic methods that can be applied to ILPs include