Java中Dijkstra算法需要帮助

本文介绍了Java中Dijkstra算法需要帮助的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述 我很难理解这些代码。 Hi, I have difficulty understanding these code.import java.util.PriorityQueue;import java.util.List;import java.util.ArrayList;import java.util.Collections;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 Dijkstra {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 ufor (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 };computePaths(v0);for (Vertex v : vertices) {System.out.println("Distance to " + v + ": " + v.minDistance);List<Vertex> path = getShortestPathTo(v);System.out.println("Path: " + path);}}} main方法中的部分computePaths（v0）; v0是来源，如果我想继续并找到v1'到达所有目的地的最短路径，我所做的就是复制相同的for循环和将源更改为v1。 这就是我所做的，但它不起作用，因为它仍然获得v0的最短路径。 br $> b $ b The part in the main method computePaths(v0);v0 is the source, and if i want to continue and find v1''s shortest path to all destination, what i have done is by copying the same for loop and change the source to "v1".This is what i have done, but it does not work as it is still obtaining the v0''s shortest path.computePaths(v1);for (Vertex v : vertices) {System.out.println("Distance to " + v + ": " + v.minDistance);List<Vertex> path = getShortestPathTo(v);System.out.println("Path: " + path); 能帮助我解决这个问题的任何一种灵魂？Any kind souls able to help me fix this issue?推荐答案 看看在算法的文字描述中可以找到这里 [ ^ ]带有一些不错的动画。 如果您不喜欢这种解释，Google非常乐于助人...... Have a look at the text description of the algorithm, which can be found here[^] with some nice animation.If you don''t like that explanation, Google is quite helpful... 这篇关于Java中Dijkstra算法需要帮助的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！