1,721,062 research outputs found
Near real-time suffix tree construction via the fringe marked ancestor problem
No full textAbstractWe contribute a further step towards the plausible real-time construction of suffix trees by presenting an on-line algorithm that spends only O(loglogn) time processing each input symbol and takes O(nloglogn) time in total, where n is the length of the input text. Our results improve on a previously published algorithm that takes O(logn) time per symbol and O(nlogn) time in total. The improvements are obtained by adapting Weinerʼs suffix tree construction algorithm to use a new data structure for the fringe marked ancestor problem, a special case of the nearest marked ancestor problem, which may be of independent interest
On a facility location problem with applications to tele-diagnostic
No full textConsider an undirected graph G modelling a network. Each vertex in the graph contains some physical devices, which can be monitored and possibly repaired from a remote site in case they become faulty. We assume that there can be two kinds of faults in the system: soft faults, which can be repaired remotely from another site (i.e., a monitor), and severe faults which cannot be repaired remotely and require further (possibly human) interventions. We assume that soft faults happen with some fixed probability λ, 0 < λ ≤ 1. We investigate the problem of locating monitors in the network so as to minimize the total expected communication cost per fault. We formalize such a problem as a location problem with a cost function depending on λ and study some properties of the optimal solutions. The latter are exploited for investigating the complexity of the problem and providing efficient approximation algorithms
- …
