commit

Author: 1367356

.metadata/.plugins/org.eclipse.core.resources/.history/10/00e2e322aba500171316854707a54be9

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+package breadth_first_search;
+
+import java.awt.image.SampleModel;
+import java.io.InputStream;
+import java.text.DecimalFormat;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Scanner;
+
+import RepresentationGraph.Graph;
+import RepresentationGraph.Graph.Node;
+
+public class BreadthFirstSearch {
+	protected Node[] graph; // 以数组的方式存储图，需要初始化指定数组的长度
+	protected List<Node> list = new ArrayList<Node>(); // 以数组列表的形式存放图，可以不用初始化，直接添加
+	Graph graphObj=new Graph(100,0);
+	protected int maxSize;
+	protected int gSize;
+	public int count = 1;
+	public double[][] weights;
+	double[] smallWeight;
+	
+	public BreadthFirstSearch(int maxSize, int gSize) {
+		this.maxSize = maxSize;
+		this.gSize = gSize;
+		graph = new Node[maxSize];
+	}
+
+	/**
+	 * 图中的节点
+	 * 
+	 * @author liyafei
+	 * 
+	 * @param <> 节点中的泛型 有三个属性，下一节点，关键字，两个节点之间的权重， 权重应该以矩阵的方式存储（也就是一个二维数组）
+	 *        可以使用一个开始值（start）和结束值(end)来代表权重(weight)是哪两个节点的。
+	 *        例如：start=2，end=4,weight=8,那么表示2号节点和4号节点之间的权重值为8；
+	 *        可以在data.txt里面每个相邻节点后面跟上权重值。 如果求最短距离时，可以用sumWeight记录到该节点总距离的最短距离
+	 *			在执行广度优先搜索或者深度优先搜索时，可以用color标记每个节点的颜色，代表每个节点是否已经被搜索过。
+	 */
+	public class Node {
+		double weight;
+		Node link;
+		int key;
+		int start;
+		int end;
+		double sumWeight=0;
+		String color="WHITE";
+	}
+
+	/**
+	 * 得到创建的带有权重的图，读出相邻节点之间的距离，然后存储到二维数组weights中。
+	 * 权重图的大小比节点多1，但是角标为0的位置都没用，为了处理存储的位置与节点的编号相一致
+	 */
+	public double[][] getWeightArray(){
+		weights=new double[list.size()][list.size()];
+		for (int i = 0; i < list.size(); i++) {
+			Node node=(Node) list.get(i);
+			while(node!=null){
+			int row=node.start-1;
+			int col=node.end-1;
+			double weight=node.weight;
+			weights[row][col]=weight;
+			node=node.link;
+			}
+		}
+		return weights;
+	}
+	
+	/**
+	 * 根据权重数组，求最短路径。
+	 */
+	public void shortestPathOfBFS(int vertex){
+		int v=0;  //定义一个常量，用于记录最小点数
+		double minWeight;//定义一个常量，记录最小权重
+		double[][] weis=getWeightArray();
+		int vertexNum=weis.length;
+		int k=weis[vertex].length;
+		smallWeight=new double[k];
+		for (int i = 0; i < smallWeight.length; i++) {
+			smallWeight[i]=weights[vertex][i];
+		}
+		boolean[] weightFound=new boolean[vertexNum];
+		for (int i = 0; i < weightFound.length; i++) {
+			weightFound[i]=false;
+		}
+		weightFound[vertex]=true;
+		smallWeight[vertex]=0; //源节点到源节点的距离设为0
+		
+		for (int i = 0; i < weightFound.length; i++) {
+			minWeight=Double.MAX_VALUE;
+			for (int j = 0; j < weightFound.length; j++) {
+				if(!weightFound[j]){
+					if(smallWeight[j]<minWeight){
+						v=j;
+						minWeight=smallWeight[v];
+					}
+					weightFound[j]=true;
+				}
+			}
+			for (int j = 0; j < weightFound.length; j++) {
+				if(!weightFound[j]){
+					if(minWeight+weis[v][j]<smallWeight[j]){
+						smallWeight[j]=minWeight+weis[v][j];
+					}
+				}
+			}
+		}
+		
+	}
+	
+	public void printShortestPathOfBFS(int vertex){
+		DecimalFormat twoDigits=new DecimalFormat("0.00");
+		System.out.println("source vertex"+vertex);
+		System.out.println("shortest distance from the source to each vertex");
+		for (int i = 0; i < list.size(); i++) {
+			System.out.println("  "+i+"\t\t"+twoDigits.format(smallWeight[i]));
+			System.out.println(" ");
+		}
+	}
+	
+	/**
+	 * 得到链表的长度
+	 * @param node
+	 * @return
+	 */
+	public int getLength(Node node){
+		int length=0;
+		while(node.link!=null){
+			node=node.link;
+			length++;
+		}
+		return length;
+	}
+
+	/**
+	 * 创建图，以链表的方式创建图
+	 * 
+	 * @return 返回图的链表形式，其中数组中每个位置是一个顶点的链表
+	 */
+	// public Node[] createGraph(){
+	public List createGraph() {
+		Class clazz = this.getClass();
+		InputStream ins = clazz.getResourceAsStream("/data.txt"); // 通过外部数据创建链表,使用/加载src目录下的文件
+																	// 不使用/是加载类路径下的文件
+		Scanner scanner = new Scanner(ins); // 流输入。
+		while (scanner.hasNextLine()) {
+			String s = scanner.nextLine();
+			Scanner oneLine = new Scanner(s);
+			Node first = null;
+			Node newNode = null, last = null;
+			while (oneLine.hasNext()) {
+				String s1 = oneLine.next();
+
+				int num = Integer.parseInt(s1);
+				if (num == 999)
+					break;
+				newNode = new Node();
+
+				if (first != null && oneLine.hasNext()) { // 创建first之后，读取下一节点时再读取权重
+					String s2 = oneLine.next();// 读取权重
+					double weight = Double.parseDouble(s2);
+					newNode.weight = weight;
+					newNode.end = num;
+				}
+
+				// newNode.key=num; // 被 newNode.end=num;代替了
+
+				newNode.start = count;
+
+				newNode.link = null;
+				if (first == null) {
+					newNode.weight = 0;
+					newNode.end = count;
+					first = newNode;
+					last = newNode;
+				} else {
+					last.link = newNode;
+					last = newNode;
+				}
+			}
+			graph[count] = first;
+			list.add(first);
+			count++;
+		}
+		return list;
+	}
+	
+	/**
+	 * 打印构建的图，起始节点，终止节点，起始节点到终止节点的权重
+	 */
+	public void printGraph(){
+		for (int i = 0; i < list.size(); i++) {
+			Node node=(Node) list.get(i);
+			System.out.println("以第"+(i+1)+"个节点为头节点的链表");
+			//System.out.println(node.key);
+			while(node!=null){
+			System.out.print("起始节点"+node.start+"        ");
+			System.out.print("终止节点"+node.end+"           ");
+			System.out.println("起始节点到终止节点的权重"+node.weight);
+			node=node.link;
+			}
+		}
+	}
+	/**
+	 * 打印权重图
+	 */
+	public void printWeightGraph(){
+		double[][] weightsArray=getWeightArray();
+		for (int i = 0; i < weightsArray.length; i++) {
+			System.out.println();
+			double[] wa=weightsArray[i];
+			for (int j = 0; j < wa.length; j++) {
+				System.out.print(wa[j]+"    ");
+			}
+			
+		}
+	}
+
+}