Java data structure and algorithm------diagram (Shortest path Dijkstra)

1  PackageiYou.neugle.graph;2 3 Importjava.util.ArrayList;4 Importjava.util.List;5 6 //The code to create the diagram procedure is in the blog post of the diagram, which is used directly here7  Public classDijkstra {8     PrivateMYGRAPH1 graph;9     Private intstart;Ten     Private intMaxnum; One     Private int[] distance;//starting point to end distance A     Private int[] point;//collection of other points except the starting point -     Privatestring[] path;//the path from the starting point to the endpoint -     Privatelist<integer> s =NewArraylist<integer> ();//the collection of points the  -      PublicDijkstra (MyGraph1 graph,intstart) { -          This. Graph =graph; -          This. Start = Start-1; +          This. Maxnum = This. Graph.getgraph (). Maxnum; -Distance =New int[ This. maxNum-1]; +Point =New int[ This. maxNum-1]; APath =Newstring[ This. maxNum-1]; at     } -  -     //Initialize minimum distance array -     Private voidInit () { -          for(inti = 0; I < This. maxNum-1; i++) { -              This. distance[i] =Integer.max_value; in             if(I >= This. Start) { -                  This. point[i] = i + 1; to}Else { +                  This. point[i] =i; -             } the         } *     } $ Panax Notoginseng      Public voidDijkstracore () { -          This. Init (); the         //first add the starting node to the set S +          This. S.add ( This. Start); A         //Initialize Intermediate node u the         intU = This. Start; +         //Terminate if s set reaches Maxnum -          while(S.size () < This. Maxnum) { $             int[] edges = This. Graph.getgraph (). Edge; $             Booleanb =false; -              for(inti = 0; i < edges[u].length; i++) { -                 //if the start node and the middle node are not connected to the general rule no action is made (excluding the start node) the                 if(edges[ This. start][u] = = 0 && u! = This. Start) { -                      Break;Wuyi                 } the                 //The distance from the node to the starting point is not to be asked. -                 if(i = = This. Start) { Wub =true; -                     Continue; About                 } $                 intx; -                 //If the node after the starting node requires i-- -                 if(b = =false) { -x =i; A}Else { +x = i-1; the                 } -                 //If there is a path, the calculation $                 if(edges[u][i]! = 0) { the                     inttemp = edges[ This. Start][u] +Edges[u][i]; the                     if(Temp < This. Distance[x]) { the                          This. distance[x] =temp; the                         if( This. Start = =u) { -                              This. path[x] = ( This. Start + 1) + "+" + (i + 1); in}Else { the                              This. path[x] = ( This. Start + 1) + "+" + (U + 1) the+ "+" + (i + 1); About                         } the                     } the                 } the             } +             //find the next intermediate node -U = This. Function (); the             //add an intermediate point to the set SBayi              This. S.add (u); the         } the          This. Print (); -     } -  the     //function function: Find the minimum value in the distance array at this time (the condition of the minimum value is not the minimum value in s) the     Private intFunction () { the         intU =Integer.max_value; the         intK =-1; -          for(inti = 0; I < This. distance.length; i++) { the             //If the node exists in S, continue to find other minor nodes the             if( This. S.contains ( This. Point[i])) { the                 Continue;94}Else { the                 if( This. Distance[i] <u) { theU = This. Distance[i]; theK = This. Point[i];98                 } About             } -         }101         returnK;102     }103 104     //Print Results the     Private voidPrint () {106          for(inti = 0; I < This. distance.length; i++) {107System.out.println ( This. Path[i] + ":" + This. Distance[i]);108         }109     } the 111      Public Static voidMain (string[] args) { theMYGRAPH1 graph =NewMYGRAPH1 (5, 0);113Graph. Createmaxtrixgraph (1, 2, 2); theGraph. Createmaxtrixgraph (1, 3, 5); theGraph. Createmaxtrixgraph (1, 5, 3); theGraph. Createmaxtrixgraph (2, 4, 4);117Graph. Createmaxtrixgraph (3, 5, 5);118Graph. Createmaxtrixgraph (4, 5, 2);119 graph. Outputmaxtrixgraph (); -Dijkstra Dijkstra =NewDijkstra (graph, 2);121 Dijkstra. Dijkstracore ();122     }123}

  1 2 3 4 5 1 0 2 5 0 3 2 2 0 0 4 0 3 5 0 0 0 5 4 0 4 0 0 2 5 3 0 5 2 0 2->1:22->1->3:72->4:42->1->5:5

Java data structure and algorithm------diagram (Shortest path Dijkstra)