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Negative ring: Because the negative ring must be shorter and shorter, but when all points on a graph are selected, it must not be the shortest path. Therefore, we can think about how to deal with negative rings from this point: The only way to deal with negative rings is \ (\ text{SPFA} \), \ (\ text{dijkstra} \) is not available. When we updat ...

A basic union search set There are only two operations for the basic union query set, one is to find ancestors, and the other is to merge int find(int x) { if(x==pre[x]) return x; else return pre[x]=find(pre[x]); } void join(int x,int y) { pre[find(x)]=find(y); } Two weighted union search set   for weighted concurrent sear ...

General idea of the topic Someone put f l o y d floyd floyd is written as follows. How many more digraphs are there d ...

On the right side of the page, there is a directory index, which can jump to the content you want to see according to the titleIf not on the right, look for the left Main article: https://blog.csdn.net/grd_java/article/details/120526149 Why is there a map Linear table and tree, linear table is limited to a direct precursor and a direct suc ...

catalogue 🌠DFS 🌠BFS 🌠 Breadth first traversal of trees and graphs → topological sorting Example: 🌠 shortest path   👉 Single source shortest path (naive Dijkstra) (there must be no negative weight edge) → heap optimization Dijkstra (to be continued...) 👉 Single source shortest path with negative weight edge (Bellm ...

Acwing 1170. Layout meaning of the title Cows like to stand close to their friends when waiting in line for feeding. Farmer John has N N N cows, number from 1 1 1 to ...

catalogue shortest path Plain Dijkstra minimum spanning tree Prim   algorithm Kruskal algorithm   shortest path Plain Dijkstra Time complexity:          O(n2+m) , n   Represents the number of points, M   Represents the number of sides Dense graph 👉    &nbs ...

On differential constraint It's still a difficult thing. introduce Consider a limitation A i ≤ x i + ...

General idea of the topic Main idea of the title: Problem solving ideas: First, we must find the shortest path between any two points → F l o y e ...