par Ito, Hiro;Langerman, Stefan ;Yoshida, Yuichi
Référence Lecture notes in computer science, 7288 LNCS, page (235-244)
Publication Publié, 2012
Article révisé par les pairs
Résumé : Three men, each with a sister, must cross a river using a boat which can carry only two people, so that a woman whose brother is not present is never left in the company of another man. This is a very famous problem appeared in Latin book "Problems to Sharpen the Young," one of the earliest collections on recreational mathematics. This paper considers a generalization of such "River-Crossing Problems." It shows that the problem is NP-hard if the boat size is three, and a large class of sub-problems can be solved in polynomial time if the boat size is two. It's also conjectured that determining whether a river crossing problem has a solution without bounding the number of transportations, can be solved in polynomial time even when the size of the boat is large. © 2012 Springer-Verlag Berlin Heidelberg.