码迷,mamicode.com
首页 > 其他好文 > 详细

图的遍历(DFS、BFS)

时间:2014-10-04 21:27:27      阅读:432      评论:0      收藏:0      [点我收藏+]

标签:style   blog   http   color   io   ar   java   for   sp   

理论:

bubuko.com,布布扣

 

深度优先搜索(Depth_Fisrst Search)遍历类似于树的先根遍历,是树的先根遍历的推广:

bubuko.com,布布扣

广度优先搜索(Breadth_First Search) 遍历类似于树的按层次遍历的过程:

bubuko.com,布布扣

 

java实现

Vertex.java

package 图;

public class Vertex{
    String value;
    boolean isVisited;
    Vertex(String value)
    {
        this.value=value;
        this.isVisited=false;
    }
    public String getValue() {
        return value;
    }
    public void setValue(String value) {
        this.value = value;
    }
    public boolean isVisited() {
        return isVisited;
    }
    public void setVisited(boolean isVisited) {
        this.isVisited = isVisited;
    }
    
}

 

Edge.java

package 图;


public class Edge{
    Vertex start;
    Vertex end;
    int value;
    public Vertex getStart() {
        return start;
    }

    public void setStart(Vertex start) {
        this.start = start;
    }

    public Vertex getEnd() {
        return end;
    }

    public void setEnd(Vertex end) {
        this.end = end;
    }

    public int getValue() {
        return value;
    }

    public void setValue(int value) {
        this.value = value;
    }

    Edge(Vertex start,Vertex end, int value){
        this.start=start;
        this.end=end;
        this.value=value;
    }
}

 

Graph.java

 

package 图;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import java.util.Stack;


public class Graph {
    
    public static List<Vertex> vertexList=new ArrayList<Vertex>();
    public static List<Edge> EdgeQueue=new ArrayList<Edge>();public static List<Vertex> depthVertexQueue=new ArrayList<Vertex>();
    public static List<Vertex> breathVertexQueue=new ArrayList<Vertex>();
    
    public static void buildGraph(){
        Vertex a=new Vertex("a");
        vertexList.add(a);
        Vertex b=new Vertex("b");
        vertexList.add(b);
        Vertex c=new Vertex("c");
        vertexList.add(c);
        Vertex d=new Vertex("d");
        vertexList.add(d);
        Vertex e=new Vertex("e");
        vertexList.add(e);
        Vertex f=new Vertex("f");
        vertexList.add(f);
        
        
        addEdge(a,b,0);
        addEdge(a,c,0);
        addEdge(b,d,0);
        addEdge(b,e,0);
        addEdge(c,f,0);
        
    }
    
    public static void addEdge(Vertex start,Vertex end,int value){
        Edge e=new Edge(start,end,value);
        EdgeQueue.add(e);
    }

public static Vertex getFirstUnvisitedNeighbor(Vertex origin){ Vertex unvisitedNeighbor=null; Iterator<Edge> iterator=EdgeQueue.iterator(); while(iterator.hasNext()) { Edge edge=iterator.next(); if(edge.getStart()==origin) { if(!edge.getEnd().isVisited) { unvisitedNeighbor=edge.getEnd(); break; } } } return unvisitedNeighbor; } public static void depthFirstVisit(Vertex origin){ if(origin==null) return; depthVertexQueue.add(origin); origin.setVisited(true); Vertex curVertex=origin; Stack<Vertex> stack=new Stack<Vertex>(); stack.add(curVertex); while(!stack.isEmpty()) { curVertex=stack.peek(); Vertex tempVertex=getFirstUnvisitedNeighbor(curVertex); if(tempVertex!=null) { depthVertexQueue.add(tempVertex); tempVertex.setVisited(true); stack.push(tempVertex); } else { stack.pop(); } } } public static void breathFirstVisit(Vertex origin){ if(origin==null) return; breathVertexQueue.add(origin); origin.setVisited(true); List<Vertex> list=new ArrayList<Vertex>(); Vertex curVertex=origin; list.add(curVertex); while(!list.isEmpty()) { curVertex=list.remove(0); while(getFirstUnvisitedNeighbor(curVertex)!=null) { Vertex tempVertex=getFirstUnvisitedNeighbor(curVertex); breathVertexQueue.add(tempVertex); tempVertex.setVisited(true); list.add(tempVertex); } } } public static void main(String[] args) { buildGraph(); depthFirstVisit(vertexList.get(0)); for(Vertex each:depthVertexQueue) System.out.print(each.getValue()+" "); } }

 

图的遍历(DFS、BFS)

标签:style   blog   http   color   io   ar   java   for   sp   

原文地址:http://www.cnblogs.com/huangcongcong/p/4006209.html

(0)
(0)
   
举报
评论 一句话评论(0
登录后才能评论!
© 2014 mamicode.com 版权所有  联系我们:gaon5@hotmail.com
迷上了代码!