JAVA實現DIJKSTRA演算法

標籤：rgs   list   util   test   begin   set   algo   tab   end   

import java.util.Queue;import java.util.LinkedList;public class dijkstra{  public static void main(String args[]){    System.out.println("dijkstra algo");    /*construct the adjacent table begin*/      Node n0 = new Node(0);      Node n1 = new Node(1);      Node n2 = new Node(2);      Node n3 = new Node(3);      Node n4 = new Node(4);      Node n5 = new Node(5);      AdjNode n0n1 = new AdjNode(7,n1);      AdjNode n0n2 = new AdjNode(9,n2);      AdjNode n0n5 = new AdjNode(14,n5);            AdjNode n1n0 = new AdjNode(7,n0);      AdjNode n1n2 = new AdjNode(10,n2);      AdjNode n1n3 = new AdjNode(15,n3);      AdjNode n2n0 = new AdjNode(9,n0);      AdjNode n2n5 = new AdjNode(2,n5);      AdjNode n2n3 = new AdjNode(11,n3);            AdjNode n3n1 = new AdjNode(15,n1);      AdjNode n3n2 = new AdjNode(11,n2);      AdjNode n3n4 = new AdjNode(6,n4);            AdjNode n4n3 = new AdjNode(6,n3);      AdjNode n4n5 = new AdjNode(9,n5);            AdjNode n5n4 = new AdjNode(9,n4);      AdjNode n5n2 = new AdjNode(2,n2);      AdjNode n5n0 = new AdjNode(14,n0);            AdjNode[] n0adj = {n0n1,n0n2,n0n5};      AdjNode[] n1adj = {n1n0,n1n2,n1n3};      AdjNode[] n2adj = {n2n0,n2n5,n2n3};      AdjNode[] n3adj = {n3n1,n3n2,n3n4};      AdjNode[] n4adj = {n4n3,n4n5};      AdjNode[] n5adj = {n5n4,n5n2,n5n0};      n0.addAdjNodes(n0adj);      n1.addAdjNodes(n1adj);      n2.addAdjNodes(n2adj);      n3.addAdjNodes(n3adj);      n4.addAdjNodes(n4adj);      n5.addAdjNodes(n5adj);      /*construct the adjacent table end*/      Node[] G = {n0,n1,n2,n3,n4,n5};            Queue<Node> queue = new LinkedList<Node>();      AdjNode[] currAdjNodes;      n0.color = 1;      n0.vt++;      n0.setShortestPathLen(0);      queue.offer(n0);      Node currNode = queue.poll();    while(currNode != null){        currAdjNodes = currNode.getAllAdjNodes();                for(int i=0;i<currAdjNodes.length;i++){            if(currAdjNodes[i].adjNode.getShortestPathLen() > (currNode.getShortestPathLen()+currAdjNodes[i].weight)){                  currAdjNodes[i].adjNode.setShortestPathLen(currNode.getShortestPathLen()+currAdjNodes[i].weight);                  currAdjNodes[i].adjNode.setPreNode(currNode);            }          if(currAdjNodes[i].adjNode.color == 0){            currAdjNodes[i].adjNode.color = 1;            currAdjNodes[i].adjNode.vt++;            queue.offer(currAdjNodes[i].adjNode);          }            }                currNode.color = 2;      currNode = queue.poll();    }        for(int i=0;i<G.length;i++){      System.out.println("shortest path of " + i + "node:" + G[i].getShortestPathLen()+" vt:"+G[i].vt);    }  }}

public class Node{  private int index = 0,shortestPathLen = 10000;  private Node preNode = null;  private AdjNode[] nodeArray;  public int color = 0;  public int vt = 0;  public Node(int ind){    index = ind;      }    public void addAdjNodes(AdjNode[] nodes){    nodeArray = nodes;      }    public AdjNode[] getAllAdjNodes(){    return nodeArray;      }    public void setPreNode(Node n){    preNode = n;      }    public void setShortestPathLen(int len){    shortestPathLen = len;      }    public int getShortestPathLen(){    return shortestPathLen;      }}

public class AdjNode{  int weight = 0;  Node adjNode = null;  public AdjNode(int w,Node n){    adjNode = n;        weight = w;  }}

 

JAVA實現DIJKSTRA演算法