منابع مشابه
Constant Time Generation of Free Trees
An algorithm of Beyer and Hedetniemi for generating unlabeled rooted trees is extended to generate unlabeled free trees. Abstract An algorithm of Beyer and Hedetniemi for generating unlabeled rooted trees is extended to generate unlabeled free trees. “The Beyer-Hedetniemi technique is refined to produce only one member of each equivalence class of rooted trees under isomorphism of the underlyin...
متن کاملConstant Time Generation of Trees with Degree Bounds
Given a number n of vertices, a lower bound d on the diameter, and a capacity function ∆(k) ≥ 2, k = 0, 1, . . . , ⌊n/2⌋, we consider the problem of enumerating all unrooted trees T with exactly n vertices and a diameter at least d such that the degree of each vertex with distance k from the center of T is at most ∆(k). We give an algorithm that generates all such trees without duplication in O...
متن کاملConstant Time Generation of Trees with Specified Diameter
Many algorithms to generate all trees with n vertices without repetition are already known. The best algorithm runs in time proportional to the number of trees. However, the time needed to generate each tree may not be bounded by a constant, even though it is “on average”. In this paper we give a simple algorithm to generate all trees with exactly n vertices and diameter d, without repetition. ...
متن کاملParallel Generation of t-ary Trees
A parallel algorithm for generating t-ary tree sequences in reverse B-order is presented. The algorithm generates t-ary trees by 0-1 sequences, and each 0-1 sequences is generated in constant average time O(1). The algorithm is executed on a CREW SM SIMD model, and is adaptive and cost-optimal. Prior to the discussion of the parallel algorithm a new sequential generation with O(1) average time ...
متن کاملConstant-memory Iterative Generation of Special Strings Representing Binary Trees
The shapes of binary trees can be encoded as permutations having a very special property. These permutations are tree permutations, or equivalently they avoid subwords of the type 231. The generation of binary trees in natural order corresponds to the generation of these special permutations in the lexicographic order. In this paper we use a stringologic approach to the generation of these spec...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: SIAM Journal on Computing
سال: 1986
ISSN: 0097-5397,1095-7111
DOI: 10.1137/0215039