A saw-toothed chessboard, or STC for short, is a kind of chessboard whose boundary forms two staircases from left down to right without any hole inside it. A rook at square (i, j)...
Gouveia et al. [3] show how to model the Hop Constrained Minimum Spanning tree problem as Steiner tree problem on a layered graph. Following their ideas, we provide three possibil...
In this paper we present two main results about the inapproximability of the exemplar conserved interval distance problem of genomes. First, we prove that it is NP-complete to deci...
Zhixiang Chen, Richard H. Fowler, Bin Fu, Binhai Z...
Determining the maximum number of D-dimensional spheres of radius r that can be adjacent to a central sphere of radius r is known as the Kissing Number Problem (KNP). The problem ...
Sergei Kucherenko, Pietro Belotti, Leo Liberti, Ne...
Consider a single machine and a set of jobs that are available for processing at time 0. Job ¡ has a processing time ¢¤£ , a due date ¥¦£ and a weight §¨£ . We consid...