Mathematical Programming

, Volume 66, Issue 1–3, pp 181–199 | Cite as

Lattice basis reduction: Improved practical algorithms and solving subset sum problems

  • C. P. Schnorr
  • M. Euchner


We report on improved practical algorithms for lattice basis reduction. We propose a practical floating point version of theL3-algorithm of Lenstra, Lenstra, Lovász (1982). We present a variant of theL3-algorithm with “deep insertions” and a practical algorithm for block Korkin—Zolotarev reduction, a concept introduced by Schnorr (1987). Empirical tests show that the strongest of these algorithms solves almost all subset sum problems with up to 66 random weights of arbitrary bit length within at most a few hours on a UNISYS 6000/70 or within a couple of minutes on a SPARC1 + computer.


Lattice basis reduction LLL-reduction Korkin—Zolotarev reduction Block Korkin—Zolotarev reduction Shortest lattice vector problem Subset sum problem Low density subset sum algorithm Knapsack problem Stable reduction algorithm 


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Copyright information

© The Mathematical Programming Society, Inc. 1994

Authors and Affiliations

  • C. P. Schnorr
    • 1
  • M. Euchner
    • 1
  1. 1.Fachbereich Mathematik/InformatikUniversität FrankfurtFrankfurt am MainGermany

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