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Related papers: Exact Flow Sparsification Requires Unbounded Size

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We give an algorithm that, with high probability, maintains a $(1-\epsilon)$-approximate $s$-$t$ maximum flow in undirected, uncapacitated $n$-vertex graphs undergoing $m$ edge insertions in $\tilde{O}(m+ n F^*/\epsilon)$ total update time,…

Data Structures and Algorithms · Computer Science 2026-05-22 Gramoz Goranci , Monika Henzinger , Harald Räcke , A. R. Sricharan

We show the existence of O(f(c)k) sized vertex sparsifiers that preserve all edge-connectivity values up to c between a set of k terminal vertices, where f(c) is a function that only depends on c, the edge-connectivity value. This…

Data Structures and Algorithms · Computer Science 2019-10-24 Yang P. Liu , Richard Peng , Mark Sellke

Given a capacitated undirected graph $G=(V,E)$ with a set of terminals $K \subset V$, a mimicking network is a smaller graph $H=(V_H,E_H)$ that exactly preserves all the minimum cuts between the terminals. Specifically, the vertex set of…

Data Structures and Algorithms · Computer Science 2012-07-27 Arindam Khan , Prasad Raghavendra , Prasad Tetali , László A. Végh

Training sparse networks to converge to the same performance as dense neural architectures has proven to be elusive. Recent work suggests that initialization is the key. However, while this direction of research has had some success,…

Machine Learning · Computer Science 2021-06-17 Kale-ab Tessera , Sara Hooker , Benjamin Rosman

The relationship between the sparsest cut and the maximum concurrent multi-flow in graphs has been studied extensively. For general graphs with $k$ terminal pairs, the flow-cut gap is $O(\log k)$, and this is tight. But when topological…

Data Structures and Algorithms · Computer Science 2018-11-08 Robert Krauthgamer , James R. Lee , Havana Rika

The network reconfiguration problem seeks to find a rooted tree $T$ such that the energy of the (unique) feasible electrical flow over $T$ is minimized. The tree requirement on the support of the flow is motivated by operational constraints…

Data Structures and Algorithms · Computer Science 2023-08-24 Swati Gupta , Ali Khodabakhsh , Hassan Mortagy , Evdokia Nikolova

We show fixed-parameter tractability of the Directed Multicut problem with three terminal pairs (with a randomized algorithm). This problem, given a directed graph $G$, pairs of vertices (called terminals) $(s_1,t_1)$, $(s_2,t_2)$, and…

Data Structures and Algorithms · Computer Science 2024-01-11 Meike Hatzel , Lars Jaffke , Paloma T. Lima , Tomáš Masařík , Marcin Pilipczuk , Roohani Sharma , Manuel Sorge

We study vertex sparsification for preserving cuts. Given a graph $G$ with a subset $|T|=k$ of its vertices called terminals, a \emph{quality-$q$ cut sparsifier} is a graph $G'$ that contains $T$, such that, for any partition $(T_1,T_2)$ of…

Data Structures and Algorithms · Computer Science 2024-10-18 Yu Chen , Zihan Tan

A \emph{tree cut-sparsifier} $T$ of quality $\alpha$ of a graph $G$ is a single tree that preserves the capacities of all cuts in the graph up to a factor of $\alpha$. A \emph{tree flow-sparsifier} $T$ of quality $\alpha$ guarantees that…

Data Structures and Algorithms · Computer Science 2026-02-17 Daniel Agassy , Dani Dorfman , Haim Kaplan

In this paper, we focus our attention on the large capacities unsplittable flow problem in a game theoretic setting. In this setting, there are selfish agents, which control some of the requests characteristics, and may be dishonest about…

Data Structures and Algorithms · Computer Science 2008-12-18 Yossi Azar , Iftah Gamzu , Shai Gutner

We consider the problem of finding a minimum cut of a weighted graph presented as a single-pass stream. While graph sparsification in streams has been intensively studied, the specific application of finding minimum cuts in streams is less…

Data Structures and Algorithms · Computer Science 2024-12-09 Matthew Ding , Alexandro Garces , Jason Li , Honghao Lin , Jelani Nelson , Vihan Shah , David P. Woodruff

We present a general framework of designing efficient dynamic approximate algorithms for optimization on undirected graphs. In particular, we develop a technique that, given any problem that admits a certain notion of vertex sparsifiers,…

Data Structures and Algorithms · Computer Science 2020-05-06 Li Chen , Gramoz Goranci , Monika Henzinger , Richard Peng , Thatchaphol Saranurak

We consider general, steady, balanced flows of a commodity over a network where an instance of the network flow is characterized by edge flows and nodal potentials. Edge flows in and out of a node are assumed to be conserved, thus…

Optimization and Control · Mathematics 2015-04-06 Marc Vuffray , Sidhant Misra , Michael Chertkov

Flow Matching has become a cornerstone of modern generative models like Stable Diffusion 3, largely due to the efficiency of its Rectified Flow (RF) variant. The success of RF hinges on iteratively learning straight trajectories, pushing…

Machine Learning · Computer Science 2026-05-19 Vansh Bansal , Saptarshi Roy , Purnamrita Sarkar , Alessandro Rinaldo

In vertex-cut sparsification, given a graph $G=(V,E)$ with a terminal set $T\subseteq V$, we wish to construct a graph $G'=(V',E')$ with $T\subseteq V'$, such that for every two sets of terminals $A,B\subseteq T$, the size of a minimum…

Data Structures and Algorithms · Computer Science 2022-07-05 Itai Boneh , Robert Krauthgamer

Neural networks have emerged as a powerful tool for solving complex tasks across various domains, but their increasing size and computational requirements have posed significant challenges in deploying them on resource-constrained devices.…

Machine Learning · Computer Science 2023-12-05 Evan Dogariu

This paper investigates the connections between rectified flows, flow matching, and optimal transport. Flow matching is a recent approach to learning generative models by estimating velocity fields that guide transformations from a source…

Machine Learning · Computer Science 2026-02-17 Johannes Hertrich , Antonin Chambolle , Julie Delon

We present efficient deep learning techniques for approximating flow and transport equations for both single phase and two-phase flow problems. The proposed methods take advantages of the sparsity structures in the underlying discrete…

Numerical Analysis · Mathematics 2020-01-08 Yating Wang , Guang Lin

CSP sparsification, introduced by Kogan and Krauthgamer (ITCS 2015), considers the following question: how much can an instance of a constraint satisfaction problem be sparsified (by retaining a reweighted subset of the constraints) while…

Data Structures and Algorithms · Computer Science 2024-11-07 Sanjeev Khanna , Aaron L. Putterman , Madhu Sudan

We consider single-sink network flow problems. An instance consists of a capacitated graph (directed or undirected), a sink node $t$ and a set of demands that we want to send to the sink. Here demand $i$ is located at a node $s_i$ and…

Data Structures and Algorithms · Computer Science 2015-05-18 F. Bruce Shepherd , Adrian Vetta