Java通过邻接矩阵实现无向图的创建、遍历(DFS、BFS)

Java通过邻接矩阵实现无向图的创建、遍历(DFS、BFS)

边(弧)

public class ArcCell {
	int adj;
	String info;
}

关于Graph类:

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

public class Graph {
	int[] vexs;
	ArcCell[][] arcCells;
	int vexnum;
	int arcnum;
	boolean[] visited;
	
	
	final static int INFINITY = 2147483646;
	
	
	//创建一个新的无向图
	static Graph CreateUDN() {
		Scanner sc = new Scanner(System.in);
		Graph G = new Graph();
		System.out.println("请输入顶点数:");
		G.vexnum = sc.nextInt();
		System.out.println("请输入边数:");
		G.arcnum = sc.nextInt();
		
		G.vexs = new int[G.vexnum];
		G.arcCells = new ArcCell[G.vexnum][G.vexnum];
		
		System.out.println("请输入" + G.vexnum + "个顶点的信息:");
		
		for (int i = 0; i < G.vexnum; i++) {
			G.vexs[i] = sc.nextInt();
		}
		for (int i = 0; i < G.vexnum; i++) {
			for (int j = 0; j < G.vexnum; j++) {
				G.arcCells[i][j] = new ArcCell();
				G.arcCells[i][j].adj = INFINITY;
				G.arcCells[i][j].info = null;
			}
		}
		System.out.println("请输入" + G.arcnum + "个边的信息:(输入形式:顶点1    顶点2    权值)");
		for (int i = 0; i < G.arcnum; i++) {
			int a1 = sc.nextInt();
			int a2 = sc.nextInt();
			int value = sc.nextInt();
			int i1 = LocalVex(G, a1);
			int j1 = LocalVex(G, a2);
			if(i1 != -1 && j1 != -1) {
				G.arcCells[i1][j1].adj = value;
				G.arcCells[j1][i1].adj = value;
			}
		}
		System.out.println("初始化完成!");
		
		sc.close();
		return G;
	}
	
	
	//指定值的位置
	static int LocalVex(Graph G, int value) {
		for (int i = 0; i < G.vexs.length; i++) {
			if(G.vexs[i] == value) {
				return i;
			}
		}
		return -1;
	}
	//下一个点位置
	static int NextVex(Graph G, int i, int w) {
		for (int j = w + 1; j < G.vexnum; j++) {
			if(G.arcCells[i][j].adj != INFINITY && G.visited[j] == false) {
				return j;
			}
		}
		return -1;
	}


//DFS	通过递归调用实现DFS遍历
	//DFS遍历
	static void DFSTraverse(Graph G){
		G.visited = new boolean[G.vexnum];
		for (int i = 0; i < G.vexnum; i++) {
			if(!G.visited[i]) {
				DFS(G, i);
			}
		}
	}
	//DFS方法
	static void DFS(Graph G, int i){
		G.visited[i] = true;
		System.out.print(G.vexs[i] + "  ");
		for (int w = NextVex(G, i, 0); w>=0; w = NextVex(G, i, w)) {
			if(G.visited[w] == false) {
				DFS(G, w);
			}
		}
	}
	
	
//BFS	通过使用ArrayList模拟队列实现BFS遍历
	static void BFSTraverse(Graph G) {
		System.out.println();
		List<Integer> queue = new ArrayList<Integer>();
		G.visited = new boolean[G.vexnum];
		for (int i = 0; i < G.vexnum; i++) {
			if(!G.visited[i]) {
				G.visited[i] = true;
				System.out.print(G.vexs[i] + "  ");
				queue.add(i);
				while(!queue.isEmpty()) {
					int aaa = queue.remove(0);
					for(int w = NextVex(G, aaa, 0);w>=0;w = NextVex(G, aaa, w)) {
						if(!G.visited[w]) {
							G.visited[w] = true;
							System.out.print(G.vexs[w] + "  ");
							queue.add(w);
						}
					}
				}
			}
		}
	}
}
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