prims-algorithm

How to implement Prim's algorithm with a Fibonacci heap?

こ雲淡風輕ζ 提交于 2019-11-30 10:23:09
问题 I know Prim's algorithm and I know its implementation but always I skip a part that I want to ask now. It was written that Prim's algorithm implementation with Fibonacci heap is O(E + V log(V)) and my question is: what is a Fibonacci heap in brief? How is it implemented? And How can you implement Prim's algorithm with a Fibonacci heap? 回答1: A Fibonacci heap is a fairly complex priority queue that has excellent amoritzed asymptotic behavior on all its operations - insertion, find-min, and

How to implement Prim's algorithm with a Fibonacci heap?

为君一笑 提交于 2019-11-29 20:00:18
I know Prim's algorithm and I know its implementation but always I skip a part that I want to ask now. It was written that Prim's algorithm implementation with Fibonacci heap is O(E + V log(V)) and my question is: what is a Fibonacci heap in brief? How is it implemented? And How can you implement Prim's algorithm with a Fibonacci heap? A Fibonacci heap is a fairly complex priority queue that has excellent amoritzed asymptotic behavior on all its operations - insertion, find-min, and decrease-key all run in O(1) amortized time, while delete and extract-min run in amortized O(lg n) time. If you

Why can't Prim's or Kruskal's algorithms be used on a directed graph?

ε祈祈猫儿з 提交于 2019-11-28 17:57:29
Prim's and Kruskal's algorithms are used to find the minimum spanning tree of a graph that is connected and undirected. Why can't they be used on a graph that is directed? It's a minor miracle that these algorithms work in the first place -- most greedy algorithms just crash and burn on some instances. Assuming that you want to use them to find a minimum spanning arborescence (directed paths from one vertex to all others), then one problematic graph for Kruskal looks like this. 5 --> a / / ^ s 1| |2 \ v / --> b 3 We'll take the a->b arc of cost 1, then get stuck because we really wanted s->b

Difference between Prim's and Dijkstra's algorithms?

戏子无情 提交于 2019-11-28 15:04:16
What is the exact difference between Dijkstra's and Prim's algorithms? I know Prim's will give a MST but the tree generated by Dijkstra will also be a MST. Then what is the exact difference? templatetypedef Prim's algorithm constructs a minimum spanning tree for the graph, which is a tree that connects all nodes in the graph and has the least total cost among all trees that connect all the nodes. However, the length of a path between any two nodes in the MST might not be the shortest path between those two nodes in the original graph. MSTs are useful, for example, if you wanted to physically

Why can't Prim's or Kruskal's algorithms be used on a directed graph?

和自甴很熟 提交于 2019-11-27 20:13:19
问题 Prim's and Kruskal's algorithms are used to find the minimum spanning tree of a graph that is connected and undirected. Why can't they be used on a graph that is directed? 回答1: It's a minor miracle that these algorithms work in the first place -- most greedy algorithms just crash and burn on some instances. Assuming that you want to use them to find a minimum spanning arborescence (directed paths from one vertex to all others), then one problematic graph for Kruskal looks like this. 5 --> a /

When should I use Kruskal as opposed to Prim (and vice versa)?

萝らか妹 提交于 2019-11-27 16:35:29
I was wondering when one should use Prim's algorithm and when Kruskal's to find the minimum spanning tree? They both have easy logics, same worst cases, and only difference is implementation which might involve a bit different data structures. So what is the deciding factor? Use Prim's algorithm when you have a graph with lots of edges. For a graph with V vertices E edges, Kruskal's algorithm runs in O(E log V) time and Prim's algorithm can run in O(E + V log V) amortized time, if you use a Fibonacci Heap . Prim's algorithm is significantly faster in the limit when you've got a really dense

When should I use Kruskal as opposed to Prim (and vice versa)?

丶灬走出姿态 提交于 2019-11-26 18:42:44
问题 I was wondering when one should use Prim's algorithm and when Kruskal's to find the minimum spanning tree? They both have easy logics, same worst cases, and only difference is implementation which might involve a bit different data structures. So what is the deciding factor? 回答1: Use Prim's algorithm when you have a graph with lots of edges. For a graph with V vertices E edges, Kruskal's algorithm runs in O(E log V) time and Prim's algorithm can run in O(E + V log V) amortized time, if you