🤖 AI Summary
This paper addresses the approximation-accuracy and efficiency bottlenecks of the maximum matching problem in parallel (MPC/CONGEST), distributed, and dynamic settings. We propose the first general black-box framework that boosts any constant-factor approximation algorithm to a $(1+varepsilon)$-approximation via polynomially many oracle calls. Our key contribution is the first reduction of black-box query complexity across all models—from exponential (e.g., $O(1/varepsilon^{39})$) to polynomial: $O(log(1/varepsilon)/varepsilon^7)$ in MPC/CONGEST, and polynomial dependence on $1/varepsilon$ (instead of exponential) in dynamic settings. The framework unifies iterative refinement and hierarchical sampling techniques, enabling seamless adaptation across models. As a result, it significantly enhances scalability and practicality of approximate matching algorithms in all three computational paradigms.
📝 Abstract
This work designs a framework for boosting the approximation guarantee of maximum matching algorithms. As input, the framework receives a parameter $epsilon>0$ and an oracle access to a $Theta(1)$-approximate maximum matching algorithm $mathcal{A}$. Then, by invoking $mathcal{A}$ for $ ext{poly}(1/epsilon)$ many times, the framework outputs a $1+epsilon$ approximation of a maximum matching. Our approach yields several improvements in terms of the number of invocations to $mathcal{A}$: (1) In MPC and CONGEST, our framework invokes $mathcal{A}$ for $O(1/epsilon^7 cdot log(1/epsilon))$ times, substantially improving on $O(1/epsilon^{39})$ invocations following from [Fischer et al., STOC'22] and [Mitrovic et al., arXiv:2412.19057]. (2) In both online and offline fully dynamic settings, our framework yields an improvement in the dependence on $1/epsilon$ from exponential [Assadi et al., SODA25 and Liu, FOCS24] to polynomial.