Hardness of approximation in P via short cycle removal: cycle detection, distance oracles, and beyond

A Abboud, K Bringmann, S Khoury… - Proceedings of the 54th …, 2022 - dl.acm.org
We present a new technique for efficiently removing almost all short cycles in a graph
without unintentionally removing its triangles. Consequently, triangle finding problems do …

Improved Roundtrip Spanners, Emulators, and Directed Girth Approximation

A Harbuzova, C Jin, VV Williams, Z Xu - Proceedings of the 2024 Annual ACM …, 2024 - SIAM
Roundtrip spanners are the analog of spanners in directed graphs, where the roundtrip
metric is used as a notion of distance. Recent works have shown existential results of …

Algorithmic trade-offs for girth approximation in undirected graphs

A Kadria, L Roditty, A Sidford, VV Williams… - Proceedings of the 2022 …, 2022 - SIAM
We present several new efficient algorithms for approximating the girth, g, of weighted and
unweighted n-vertex, m-edge undirected graphs. For undirected graphs with polynomially …

Optimal girth approximation for dense directed graphs

S Chechik, G Lifshitz - Proceedings of the 2021 ACM-SIAM Symposium on …, 2021 - SIAM
In this paper we provide a Õ (n 2) time algorithm that computes a 2-multiplicative
approximation of the girth of an n-node m-edge directed graph with non-negative edge …

Conditionally optimal approximation algorithms for the girth of a directed graph

M Dalirrooyfard, VV Williams - arXiv preprint arXiv:2004.11445, 2020 - arxiv.org
It is known that a better than $2 $-approximation algorithm for the girth in dense directed
unweighted graphs needs $ n^{3-o (1)} $ time unless one uses fast matrix multiplication …

Fully dynamic algorithms for minimum weight cycle and related problems

A Karczmarz - arXiv preprint arXiv:2106.11744, 2021 - arxiv.org
We consider the directed minimum weight cycle problem in the fully dynamic setting. To the
best of our knowledge, so far no fully dynamic algorithms have been designed specifically …

On Diameter Approximation in Directed Graphs

A Abboud, M Dalirrooyfard, R Li… - arXiv preprint arXiv …, 2023 - arxiv.org
Computing the diameter of a graph, ie the largest distance, is a fundamental problem that is
central in fine-grained complexity. In undirected graphs, the Strong Exponential Time …

AORM: Fast incremental arbitrary-order reachability matrix computation for massive graphs

SS Kim, YK Kim, YM Kang - IEEE Access, 2021 - ieeexplore.ieee.org
Processing a reachability query in large-scale networks using existing methods remains one
of the most challenging problems in graph mining. In this paper, we propose a novel …

Faster approximation algorithms for computing shortest cycles on weighted graphs

G Ducoffe - SIAM Journal on Discrete Mathematics, 2021 - SIAM
Given an n-vertex m-edge graph G with nonnegative edge-weights, a shortest cycle is one
minimizing the sum of the weights on its edges. The girth of G is the weight of a shortest …

Improved Sourcewise Roundtrip Spanners with Constant Stretch

E Stafford, C Zhu - International Computing and Combinatorics …, 2023 - Springer
Graph spanners are a sparse subgraph of a graph such that shortest-path distances for all
pairs of vertices are approximately preserved with a factor called stretch, and roundtrip …