| Depth-limited search Jul 6th 2020, 14:33, by Блоги о промышленности на Complexdoc In computer science depth-limited search is an algorithm to explore the vertices of a graph. It is a modification of depth-first search and is used for example in the iterative deepening depth-first search algorithm. General Like the normal depth-first search, depth-limited search is an uninformed search. It works exactly like depth-first search, but avoids its drawbacks regarding completeness by imposing a maximum limit on the depth of the search. Even if the search could still expand a vertex beyond that depth, it will not do so and thereby it will not follow infinitely deep paths or get stuck in cycles. Therefore depth-limited search will find a solution if it is within the depth limit, which guarantees at least completeness on all graphs. Algorithm (informal) Determine the vertex where the search should start and assign the maximum search depth Check if the current vertex is the goal state If not: Do nothing If yes: return Check if the current vertex is within the maximum search depth If not: Do nothing If yes: Expand the vertex and save all of its successors in a stack Call DLS recursively for all vertices of the stack and go back to Step 2 Pseudocode DLS(node, goal, depth) { if ( depth >= 0 ) { if ( node == goal ) return node for each child in expand(node) DLS(child, goal, depth-1) } } Properties Space complexity Since depth-limited search internally uses depth-first search, the space complexity is equivalent to that of normal depth-first search. Time complexity Since depth-limited search internally uses depth-first-search, the time complexity is equivalent to that of normal depth-first search, and is O() where stands for the number of vertices and for the number of edges in the explored graph. Note that depth-limited search does not explore the entire graph, but just the part that lies within the specified bound. Completeness Even though depth-limited search cannot follow infinitely long paths, nor can it get stuck in cycles, in general the algorithm is not complete since it does not find any solution that lies beyond the given search depth. But if the maximum search depth is chosen to be greater than the depth of a solution the algorithm becomes complete. Optimality Depth-limited search is not optimal. It still has the problem of depth-first search that it first explores one path to its end, thereby possibly finding a solution that is more expensive than some solution in another path. Literature
Class Search Algorithm Data structure Graph Worst case performance O( | V | + | E | )
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| Forma-Odezhda.ru on Twitter Jul 6th 2020, 14:33, by Блоги о промышленности на Complexdoc @formaodezhdaru ift.tt/3d3cq51 ›: analogindex.livejournal.com/248510.html Мужские флисовые брюки TERRA, характеризующиеся высоким комфортом и надёжным сохранением тепла. Функциональный дизайн с двумя передними карманами и регулирующим шнурком в поясе. Низ брюк собран на... LiveJournal @LiveJournal
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| Пустобрешка 🎓² Jul 6th 2020, 14:15, by Блоги о промышленности на Complexdoc
Толкования, синонимы, антонимы, переводы «Пустобрешка»
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| Изложница 🎓² Jul 6th 2020, 14:15, by Блоги о промышленности на Complexdoc
[ingot mold] металлическая форма для отливки металла в виде слитка. По конструкции изложницы подразделяют на бутылочные, глуходонные и сквозные; по способу заливки мета...
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| Альдозы 🎓² Jul 6th 2020, 14:15, by Блоги о промышленности на Complexdoc
Глицериновый альдегид простейший представитель альдоз Альдозами называют моносахариды содержащие альдегидную груп
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