Java 接受输入作为顶点
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: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
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