# Full edge-friendly index sets of complete bipartite graphs

Document Type: Research Paper

Author

Hong Kong Baptist University

Abstract

‎‎Let $G=(V,E)$ be a simple graph‎. ‎An edge labeling $f:E\to \{0,1\}$ induces a vertex labeling $f^+:V\to\Z_2$ defined by $f^+(v)\equiv \sum\limits_{uv\in E} f(uv)\pmod{2}$ for each $v \in V$‎, ‎where $\Z_2=\{0,1\}$ is the additive group of order 2‎. ‎For $i\in\{0,1\}$‎, ‎let‎ ‎$e_f(i)=|f^{-1}(i)|$ and $v_f(i)=|(f^+)^{-1}(i)|$‎. ‎A labeling $f$ is called edge-friendly if‎ ‎$|e_f(1)-e_f(0)|\le 1$‎. ‎$I_f(G)=v_f(1)-v_f(0)$ is called the edge-friendly index of $G$ under an edge-friendly labeling $f$‎. ‎The full edge-friendly index set of a graph $G$ is the set of all possible edge-friendly indices of $G$‎. ‎Full edge-friendly index sets of complete bipartite graphs will be determined‎.

Keywords

Main Subjects

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