Approximation schemes for subset-sums ratio problems

Abstract

We consider the Subset-Sums Ratio Problem (SSR), in which given a set of integers the goal is to find two subsets such that the ratio of their sums is as close to 1 as possible, and we introduce a family of variations of SSR that capture additional meaningful requirements. Our main contribution is a generic framework that yields a fully polynomial time approximation scheme (FPTAS) for problems in this family that meet certain conditions. We use our framework to design explicit FPTASs for two such problems, namely Two-Set Subset-Sums Ratio and Factor-r Subset-Sums Ratio, with running time O(n4/ε), which coincides with the best known running time for the original SSR problem [18].