such that every arc going out from x is pancyclic, and our proof yields a polynomial algorithm to nd such a vertex. Furthermore, as another consequence of our main theorem, we get a result of Alspach (Canad. Math. Bull. 10, 1967, 283{286) that states that every arc of a regular tournament is pancyclic.? 2000

Abstract not found

This book presents a unified treatment of many different kinds of planning algorithms. The subject lies at the crossroads between robotics, control theory, artificial intelligence, algorithms, and computer graphics. The particular subjects covered include motion planning, discrete planning, planning under uncertainty, sensor-based planning, visibility, decision-theoretic planning, game theory, information spaces, reinforcement learning, nonlinear systems, trajectory planning, nonholonomic planning, and kinodynamic planning.

El Salvador, Guatemala is a, study in black and white. On the left is a collection of extreme Marxist-Leninist groups led by what one diplomat calls “a pretty faceless bunch of people.’ ’ On the right is an entrenched elite that has dominated Central America’s most populous country since a CIA-backed coup deposed the reformist government of Col. Jacobo Arbenz Guzmán in 1954. Moderates of the political center. embattled but alive in E1 Salvador, have virtually disappeared in Guatemala-joining more than 30.000 victims of terror over the last tifteen vears. “The situation in Guatemala is much more serious than in EI Salvador, ” declares one Latin American diplomat. “The oligarchy is that much more reactionary. and the choices are far fewer. “ ‘Zero’: The Guatemalan oligarchs hated Jimmy Carter for cutting off U.S. military aid in 1977 to protest human-rights abuses-and the right-wingers hired marimba bands and set off firecrackers on the night Ronald Reagan was elected. They considered Reagan an ideological kinsman and believed they had a special

Let T be a hamiltonian tournament with n vertices and fl a hamiltonian cycle of T . For a cycle C k of length k in T we denote I fl (C k ) = jA(fl) " A(C k )j, the number of arcs that fl and C k have in common. Let f(n; k; T; fl) = maxfI fl (C k )jC k ae Tg and f(n; k) = minff(n; k; T; fl

Let T be a hamiltonian tournament with n vertices and fl a hamiltonian cycle of T .

is pancyclic if there exists (directed) cycles of all possible lengths; it is vertex-pancyclic if moreover the cycles can be found through any vertex. A k-tournament is strong if there is a path from u to v for each pair of distinct vertices u and v. A question posed by Gutin and Yeo about the characterization

In [4] it is conjectured that all diregular c-partite tournaments, with c ≥ 4, are pancyclic. In this paper we show that all diregular c-partite tournaments, with c ≥ 5, are in fact vertex-pancyclic.

A digraph obtained by replacing each edge of a complete multipartite graph by an arc or a pair of mutually opposite arcs with the same end vertices is called a complete multipartite digraph. Such a digraph D is called ordinary if for any pair X, Y of its partite sets the set of arcs with end

xi and distinct edges ei so that xi1 dominates xi via ei, i = 1; : : : ; `. Such a path has length `. A cycle is a path when all vertices are distinct except x0 = x`. A path (cycle) of T is Hamiltonian if it contains all vertices of T. A k-tournament T is pancyclic if it contains cycles of all