java - LinkedList Array 中每个索引的 LinkedList

Question

这里有什么问题？。我正在尝试使用邻接列表，通过利用 util 包中的集合来实现图形数据结构。这里

LinkedList array which holds some integer. Each element of that LinkedList holds another LinkedList of type: node.

但是在编译过程中，却提示类型不兼容。如何解决这个问题？

 //Sum of dependencies in a graph
import java.util.*;
class node
{
     int vertex,weight;
     public node(int v,int w)
     {
          vertex = v;
          weight = w;
     }
}
public class dependency
{
 int V;
 LinkedList<Integer> adj[];
 public dependency(int v)
 {
      V = v;
      adj = new LinkedList<Integer>[v];
      for (int i=0;i < v ;i++ ) {
           adj[i] = new LinkedList<node>();
      }
 }
 void addEdge(int v,node l)
 {
      adj[v].add(l);
 }
 void BFS(int s)
 {
      boolean visited[] = new boolean[V];
      LinkedList<Integer> queue = new LinkedList<Integer>();
      visited[s] = true;
      queue.add(s);
      while(queue.size() != 0)
      {
           s = queue.poll();
           System.out.println(s+" ");

           Iterator<Integer> i = adj[s].listIterator();
           while(i.hasNext())
           {
                int n = i.next();
                if(!visited[n])
                {
                     visited[n] = true;
                     queue.add(n);
                }
           }
      }
 }
 public static void main(String[] args) {
      graph g = new graph(4);
      node a = new node(1,10);
      node b = new node(2,20);
      node c = new node(2,30);
      node d = new node(0,20);
      node e = new node(3,30);
      node f = new node(3,20);
      g.addEdge(0, a);
      g.addEdge(0, b);
      g.addEdge(1, c);
      g.addEdge(2, d);
      g.addEdge(2, e);
      g.addEdge(3, f);

    System.out.println("Following is Breadth First Traversal "+
                       "(starting from vertex 2)");

    g.BFS(2);
 }
}

Answer 1

您已经声明了类型为 LinkedList<Integer> 的 LinkedList 数组。 ，但您正在尝试存储 LinkedList<node>在数组中。您似乎从未使用过 weight node 的属性，所以你应该改变 adj[i] = new LinkedList<node>();至adj[i] = new LinkedList<Integer>(); .