Ya-Cong Zhou

activity

20232026

collaborators

14 papers

math.CO2026

Bounds on Odd and Odd-Even Induced Subgraphs

Qiwen Guo, Gregory Gutin, Yiming Hao +3

Let $G$ be an $n$ -vertex graph and let $ℓ : V (G) \to F_{2}$ prescribe degree parities. A set $S \subseteq V (G)$ is $ℓ$ -admissible if every $v \in S$ has degree congruent to…

math.CO2026

The optimal constant for minimum weight feedback arc sets in oriented graphs

Yacong Zhou

Let $D$ be an oriented graph (a digraph with no directed 2-cycles) with maximum degree $Δ \geq 1$ , equipped with nonnegative arc weights of total weight $w (D)$ , and let $\mathrm{fas}…

math.CO2026

Weighted Counting Formula and $2 n /21$ Lower Bound for Induced Subgraphs with Prescribed Degree Parities

Gregory Gutin, Yiming Hao, Yacong Zhou

Let $G = (V, E)$ be a finite simple graph of order $n \geq 1$ , and let $ℓ : V \to {0, 1}$ be a prescribed parity labeling. A set $S \subseteq V$ is called $ℓ$ -admissible if $d_S(v)\e…

math.CO2026

A discrepancy dichotomy for 1-factorizations of signed complete bipartite graphs

Yisai Xue, Yacong Zhou

Given a signing $σ : E (K_{n, n}) \to {- 1, + 1}$ of the complete bipartite graph, when does $K_{n, n}$ admit a $1$ -factorization in which every perfect matching has discrepancy boun…

math.CO2026

Forward Arc Maximization for Hamilton Oriented Cycles and Paths in Generalizations of Tournaments

Q. Guo, G. Gutin, Y. Lan +3

Gishboliner, Krivelevich, and Michaeli (2023) conjectured the following generalization of Dirac's theorem: If the minimum degree $δ$ of an $n$ -vertex oriented graph $G$ is greater…

math.CO2025

Feedback vertex sets of digraphs with bounded maximum degree

Jiangdong Ai, Gregory Gutin, Xiangzhou Liu +2

A digraph $D$ is an oriented graph if $D$ does not have a pair of opposite arcs. The degree of a vertex $v$ of $D$ is the sum of the in-degree and out-degree of $v .$ Let $f v s (D)$ b…

Bounds on Odd and Odd-Even Induced Subgraphs

The optimal constant for minimum weight feedback arc sets in oriented graphs

Weighted Counting Formula and 2n/21 Lower Bound for Induced Subgraphs with Prescribed Degree Parities

A discrepancy dichotomy for 1-factorizations of signed complete bipartite graphs

Forward Arc Maximization for Hamilton Oriented Cycles and Paths in Generalizations of Tournaments

Feedback vertex sets of digraphs with bounded maximum degree

Weighted Counting Formula and $2 n /21$ Lower Bound for Induced Subgraphs with Prescribed Degree Parities