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; } }