图的建立(邻接矩阵)+深度优先遍历+广度优先遍历+Prim算法构造最小生成树(Java语言描述)

主要参考资料：数据结构(C语言版)严蔚敏   ，http://blog.chinaunix.net/uid-25324849-id-2182922.html   代码测试通过。

package 图的建立与实现;

import java.util.*;

public class MGraph {
	final int MAXVEX = 100;
	final int INFINITY = 65535;
	int[] vexs = new int[MAXVEX];           //顶点表
	int[][] arc = new int[MAXVEX][MAXVEX];  //边表
	boolean[] visited = new boolean[this.MAXVEX];
	int numVertexes,numEdges;
	public MGraph(){}

	public void CreateMGraph(){
		int i,j,k,w;
		System.out.println("请输入顶点数和边数：");
		Scanner scan = new Scanner(System.in);
		this.numVertexes = scan.nextInt();
		this.numEdges = scan.nextInt();
		System.out.println("请输入顶点信息，建立顶点表：");
		for(i=0; i<this.numVertexes; i++){
			this.vexs[i] = scan.nextInt();
		}
		//邻接矩阵的初始化
		for(i=0; i<this.numVertexes; i++){
			for(j=0; j<this.numVertexes; j++){
			    this.arc[i][j] = INFINITY;
			}
		}
		System.out.println("请输入边的上标、下标、权值：");
		for(k=0; k<this.numEdges; k++){
			i = scan.nextInt();
			j = scan.nextInt();
			w = scan.nextInt();
			this.arc[i][j] = w;
			this.arc[j][i] = this.arc[i][j];//如果是无向图，矩阵对称
		}

	}

	//图的深度优先遍历
	public void DFS(int i){
		int j;
		this.visited[i] = true;
		System.out.println(this.vexs[i]);
		for(j=0; j<this.numVertexes; j++){
			if(this.arc[i][j] < INFINITY && this.visited[j] == false){
				this.DFS(j);
			}
		}
	}

	public void DFSTraverse(){
		int i;
		for(i=0; i<this.numVertexes; i++){
			this.visited[i] = false;
		}
		for(i=0; i<this.numVertexes; i++){
			if(this.visited[i] == false){
				this.DFS(i);
			}
		}
	}

	//图的广度优先遍历
	public void BFSTraverse(){
		int i,j;
		Queue<Integer> queue = new ArrayDeque<Integer>();
		for(i=0; i<this.numVertexes; i++){
			this.visited[i] = false;
		}
		for(i=0; i<this.numVertexes; i++){
			if(this.visited[i] == false){
				this.visited[i] = true;
				System.out.println(this.vexs[i]);
				queue.add(i);
				while(queue.isEmpty() != true){
					i = queue.remove();
					for(j=0; j<this.numVertexes; j++){
						if(this.arc[i][j] < INFINITY  &&  visited[j] == false){
							visited[j] = true;
							System.out.println(this.vexs[j]);
							queue.add(j);
						}
					}
				}
			}
		}
	}

	//Prim算法构造最小生成树
	public void MinSpanTree_Prim(){
		 int min,i,j,k = 0;
		 int[] adjvex = new int[MAXVEX];
		 int[] lowcost = new int[MAXVEX];
		 lowcost[0] = 0;
		 adjvex[0] = 0;
		 for(i=1; i<this.numVertexes; i++){
			 lowcost[i] = this.arc[0][i];
			 adjvex[i] = 0;
			 //System.out.println(lowcost[i] + " ###");
		 }
		 for(i=1; i<this.numVertexes; i++){
			 min = INFINITY;
			 j = 1; k = 0;
			 while(j < this.numVertexes){
				 if(lowcost[j]!=0 && lowcost[j]<min){
					 min = lowcost[j];
					 k = j;
					 //System.out.println(k+ " $");
				 }
				 j++;
			 }
		System.out.printf("(%d,%d)\n",adjvex[k],k);
		 lowcost[k] = 0;
		 for(j=1; j<this.numVertexes; j++){
			 if(lowcost[j]!=0 && this.arc[k][j]<lowcost[j]){
				 lowcost[j] = this.arc[k][j];
				 adjvex[j] = k;
			 }
		   }
		 }
	}
}

package 图的建立与实现;

public class TestGraph {

	public static void main(String[] args) {
		MGraph G = new MGraph();
		G.CreateMGraph();
		System.out.println("深度优先遍历");
		G.DFSTraverse();
		System.out.println("广度优先遍历");
		G.BFSTraverse();
		System.out.println("Prim算法构造最小生成树");
		G.MinSpanTree_Prim();
	}

}