Liao, I. ChengI. ChengLiaoHSUEH-I LU2023-08-072023-08-072023-01-0101290541https://scholars.lib.ntu.edu.tw/handle/123456789/63444110 pages, 4 figuresFor an m-edge connected simple graph G, finding a spanning tree of G with the maximum number of leaves is MAXSNP-complete. The problem remains NP-complete even if G is planar and the maximal degree of G is at most four. Lu and Ravi gave the first known polynomial-time approximation algorithms with approximation factors 5 and 3. Later, they obtained a 3-approximation algorithm that runs in near-linear time. The best known result is Solis-Oba, Bonsma, and Lowski's O(m)-time 2-approximation algorithm. We show an alternative simple O(m)-time 2-approximation algorithm whose analysis is simpler. This paper is dedicated to the cherished memory of our dear friend, Professor Takao Nishizeki.Approximation algorithms | maximum-leaf spanning tree; Computer Science - Data Structures and Algorithms; Computer Science - Data Structures and Algorithms; 05C38, 05C10, 05C85, 68P05journal article10.1142/S01290541234200292-s2.0-85163212275https://api.elsevier.com/content/abstract/scopus_id/85163212275