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teaching:ip1920

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Integer Programming and Parameterized Complexity 2019/20

  1. First lecture
    • What is IP? ILP is NP-hard, but maybe restricted instances can be easier?
    • IP in fixed dimension: flatness theorem, branching, etc.
    • Building intuition using the knapsack problem and its DP. We can use DP to solve knapsack in time $O(n \cdot b)$, and to solve multidimensional knapsack in $d$ dimensions in time $O(n \cdot b^d)$. But what if $b$ is much larger than the item sizes, and/or what if we are given items by multiplicities $\mu_1, \dots, \mu_n$? Turns out we can start from some solution and then iteratively augment to the optimal solution. Each augmentation requires one DP to be solved, but this DP is simpler than the original one. In the next lecture we will formalize this.

Materials

  • A primary material is my paper An Algorithmic Theory of Integer Programming, but I will try to make the exposition here much gentler. (The paper is already long, so it tries to take a „shortest path“ approach to laying the basics.)
  • The fixed dimension part was inspired by the exposition of Fritz Eisenbrand in 50 Years of Integer Programming, pg. 515 in the linked PDF. In particular look at Section 14.8, i.e., pages 535-537. But I only expect an understanding of the basic idea of Lenstra's algorithm.
teaching/ip1920.1571060169.txt.gz · Poslední úprava: 2019/10/14 15:36 autor: Martin Koutecky