Dijkstr单元最短路径

package com.alo.offer;/** * 解决单元最短路径问题 * @author Administrator * */public class Dijkstra {static final int MAX=Integer.MAX_VALUE;    public static void main(String[] args) {        // TODO Auto-generated method stub        int[][] weight = {//邻接矩阵                {0,1,4,4},{MAX,0,1,2},{MAX,MAX,0,MAX},{MAX,MAX,MAX,0}        };        int start=0;        int[] shortPath = dijkstar(weight,start);                for(int i = 0;i < shortPath.length;i++)             System.out.println("从"+(start+1)+"出发到"+(i+1)+"的最短距离为："+shortPath[i]);                }public static int[] dijkstar(int [][]weight,int start) {int n = weight.length;int [] shortPath = new int[n]; //存放start到各顶点的最短距离int [] visited = new int[n];shortPath[start]=0;visited[start]=1;for(int i=1;i<n;i++) {int min = MAX;int k=-1;for(int j=0;j<n;j++) {if(visited[j]==0&&min>weight[start][j]) {min = weight[start][j];k = j;}}shortPath[k]=min;visited[k]=1;for(int j=0;j<n;j++) {if(visited[j]==0&&weight[k][j]!=MAX&&weight[start][k]+weight[k][j]<weight[start][j]) {weight[start][j]=weight[start][k]+weight[k][j];}}}return shortPath;}}