Java 接受输入作为顶点

Java 接受输入作为顶点,java,list,user-input,dijkstra,Java,List,User Input,Dijkstra,我正在尝试做一个计划,将有一个城市和城市之间的旅行时间列表。在程序中,我必须向用户询问起始位置和目的地。然后,程序将使用来自用户输入的信息来计算起点和终点之间的最短路径 我不知道如何让程序接受用户输入作为顶点,以便使用输入将其插入 计算路径(顶点\开始\输入\此处) System.out.println(“\n指向”+顶点\目的地\输入\此处+”:“+v1.minDistance) 列表路径=getShortestPathTo(此处的顶点\目标\输入\) 下面是我遇到问题的代码预览: Syste

我正在尝试做一个计划,将有一个城市和城市之间的旅行时间列表。在程序中,我必须向用户询问起始位置和目的地。然后,程序将使用来自用户输入的信息来计算起点和终点之间的最短路径

我不知道如何让程序接受用户输入作为顶点,以便使用输入将其插入

计算路径(顶点\开始\输入\此处)

System.out.println(“\n指向”+顶点\目的地\输入\此处+”:“+v1.minDistance)

列表路径=getShortestPathTo(此处的顶点\目标\输入\)

下面是我遇到问题的代码预览:

System.out.println("List of Cities:");
        for (Vertex v : vertices)
         {
        System.out.println(v);
        }
        Scanner k = new Scanner(System.in);
        System.out.println("\nEnter start location: ");
        Vertex start = k.nextLine();
        System.out.println("Enter destination: ");
        String destination = k.nextLine();
        
        computePaths(v0);
         System.out.println("\nDistance to " + v1 + ": " + v1.minDistance);
         List<Vertex> path = getShortestPathTo(v1);
         System.out.println("Path: " + path);
System.out.println(“城市列表”);
对于(顶点v:顶点)
{
系统输出打印Ln(v);
}
扫描仪k=新的扫描仪(System.in);
System.out.println(“\n输入起始位置:”);
顶点开始=k.nextLine();
System.out.println(“输入目的地:”);
字符串destination=k.nextLine();
计算机路径(v0);
System.out.println(“\n对“+v1+”的立场:“+v1.minDistance”);
列表路径=getShortestPathTo(v1);
System.out.println(“路径:+Path”);
整个代码如下所示:

import java.util.PriorityQueue;
import java.util.List;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;

class Vertex implements Comparable<Vertex>
{
    public final String name;
    public Edge[] adjacencies;
    public double minDistance = Double.POSITIVE_INFINITY;
    public Vertex previous;
    public Vertex(String argName) { name = argName; }
    public String toString() { return name; }
    public int compareTo(Vertex other)
    {
        return Double.compare(minDistance, other.minDistance);
    }

}


class Edge
{
    public final Vertex target;
    public final double weight;
    public Edge(Vertex argTarget, double argWeight)
    { target = argTarget; weight = argWeight; }
}

public class Lab9
{
    public static void computePaths(Vertex source)
    {
        source.minDistance = 0.;
        PriorityQueue<Vertex> vertexQueue = new PriorityQueue<Vertex>();
    vertexQueue.add(source);

    while (!vertexQueue.isEmpty()) {
        Vertex u = vertexQueue.poll();

            // Visit each edge exiting u
            for (Edge e : u.adjacencies)
            {
                Vertex v = e.target;
                double weight = e.weight;
                double distanceThroughU = u.minDistance + weight;
        if (distanceThroughU < v.minDistance) {
            vertexQueue.remove(v);

            v.minDistance = distanceThroughU ;
            v.previous = u;
            vertexQueue.add(v);
        }
            }
        }
    }

    public static List<Vertex> getShortestPathTo(Vertex target)
    {
        List<Vertex> path = new ArrayList<Vertex>();
        for (Vertex vertex = target; vertex != null; vertex = vertex.previous)
            path.add(vertex);

        Collections.reverse(path);
        return path;
    }

    public static void main(String[] args)
    {
    Vertex v0 = new Vertex("Harrisburg");
     Vertex v1 = new Vertex("Baltimore");
     Vertex v2 = new Vertex("Washington");
     Vertex v3 = new Vertex("Philadelphia");
     Vertex v4 = new Vertex("Binghamton");
     Vertex v5 = new Vertex("Allentown");
     Vertex v6 = new Vertex("New York");
     v0.adjacencies = new Edge[]{ new Edge(v1,  79.83),
                                  new Edge(v5,  81.15) };
     v1.adjacencies = new Edge[]{ new Edge(v0,  79.75),
                                  new Edge(v2,  39.42),
                                  new Edge(v3, 103.00) };
     v2.adjacencies = new Edge[]{ new Edge(v1,  38.65) };
     v3.adjacencies = new Edge[]{ new Edge(v1, 102.53),
                                  new Edge(v5,  61.44),
                                  new Edge(v6,  96.79) };
     v4.adjacencies = new Edge[]{ new Edge(v5, 133.04) };
     v5.adjacencies = new Edge[]{ new Edge(v0,  81.77),
                                  new Edge(v3,  62.05),
                                  new Edge(v4, 134.47),
                                  new Edge(v6,  91.63) };
     v6.adjacencies = new Edge[]{ new Edge(v3,  97.24),
                                  new Edge(v5,  87.94) };
     Vertex[] vertices = { v0, v1, v2, v3, v4, v5, v6 };

        
        System.out.println("List of Cities:");
        for (Vertex v : vertices)
     {
        System.out.println(v);
    }
        Scanner k = new Scanner(System.in);
        System.out.println("Enter start location: ");
        
        System.out.println("Enter destination: ");
        
        computePaths(v0);
         System.out.println("\nDistance to " + v1 + ": " + v1.minDistance);
         List<Vertex> path = getShortestPathTo(v1);
         System.out.println("Path: " + path);
    }
}
import java.util.PriorityQueue;
导入java.util.List;
导入java.util.ArrayList;
导入java.util.Collections;
导入java.util.Scanner;
类Vertex实现了可比较的
{
公共最终字符串名;
公共边缘[]邻接;
公众的双重心态=双重积极无限;
公共场所;
公共顶点(字符串argName){name=argName;}
公共字符串toString(){return name;}
公共整数比较(顶点其他)
{
返回Double.compare(minDistance,other.minDistance);
}
}
阶级边缘
{
公共最终顶点目标;
公众最终双倍权重;
公共边(顶点argTarget,双argWeight)
{target=argTarget;weight=argWeight;}
}
公共类Lab9
{
公共静态void计算路径(顶点源)
{
source.minDistance=0。;
PriorityQueue vertexQueue=新建PriorityQueue();
添加(源);
而(!vertexQueue.isEmpty()){
Vertex u=vertexQueue.poll();
//访问美国的每一个边缘
对于(边e:u.邻接)
{
顶点v=e.目标;
双倍重量=e.重量;
通过HU的双距离=u.minDistance+重量;
if(通过HU的距离
您应该将输入值分配给属性,类似于此:

Scanner in = new Scanner(System.in);
System.out.println("Enter start location: ");
location = in.nextLine();
System.out.println("Enter destination: ");
destination = in.nextLine();

System.out.println("You entered location: " + location + " and destination: " +  destination + " .");
通过使用转换后的输入值,您可以计算它们。

System.out.println(“城市列表”);
System.out.println("List of Cities:");

        for (Vertex v : vertices)
         {
        System.out.println(v);
        }
        Scanner k = new Scanner(System.in);
        System.out.println("\nEnter start location: ");
        int start = k.nextInt();
        System.out.println("Enter destination: ");
        int destination = k.nextInt();

        computePaths(vertices[start]);
         System.out.println("\nDistance to " + vertices[destination] + ": " + vertices[destination].minDistance);
         List<Vertex> path = getShortestPathTo(vertices[destination]);
         System.out.println("Path: " + path);
    }
对于(顶点v:顶点) { 系统输出打印Ln(v); } 扫描仪k=新的扫描仪(System.in); System.out.println(“\n输入起始位置:”); int start=k.nextInt(); System.out.println(“输入目的地:”); int destination=k.nextInt(); 计算路径(顶点[开始]); System.out.println(“\n指向“+顶点[destination]+”:“+顶点[destination].minDistance”); 列表路径=getShortestPathTo(顶点[目的地]); System.out.println(“路径:+Path”); }
我知道如何做到这一点,但我的问题是如何让用户输入匹配顶点,以便计算具有相邻点的最短路径?如果我只输入位置和目的地,它不会指向任何地方