Dijkstra算法

public int networkDelayTime(int[][] times, int n, int k) {
        int max=Integer.MAX_VALUE/2;
        int[][] g=new int[n][n];
        for(int i=0;i<n;i++) 
            Arrays.fill(g[i],max);
        int[] dist=new int[n];
        Arrays.fill(dist,max);
        boolean[] vis=new boolean[n];
        for(int[] time:times){
            g[time[0]-1][time[1]-1]=time[2];
        }
		//-----------------------------------------------
        dist[k-1]=0;
        for(int i=0;i<n;i++){
            int x=-1;
            for(int j=0;j<n;j++){
                if(!vis[j]&&(x==-1||dist[j]<dist[x])){
                    x=j;
                }
            }
            vis[x]=true;
            for(int j=0;j<n;j++)
                dist[j]=Math.min(dist[j],dist[x]+g[x][j]);
        }
		//-----------------------------------------------
        int ans=Arrays.stream(dist).max().getAsInt();
        return ans==max?-1:ans;
    }