#ifndef INC_05_DFS_AND_COMPONENTS_COMPONENTS_H
#define INC_05_DFS_AND_COMPONENTS_COMPONENTS_H

#include<iostream>
#include<cassert>
using namespace std;

template<typename Graph>
class Component{
private:
    Graph &G;			//传入图的引用 
    bool *visited;		//记录是否被访问过 
    int ccount;			//记录联通分支的个数 
    int *id;			//记录在哪个联通分支里 
    //深度优先遍历 
    void dfs(int v){	//对v节点进行深度优先遍历 
        
        visited[v]=true;		//设定该节点访问过 
        id[v]=ccount; 
        typename Graph::adjIterator adj(G,v);	//显式声明adjIterator为Graph中一个类型	
        for(int i=adj.begin();!adj.end();i=adj.next()){
            if(!visited[i])
                dfs(i);
        }
    } 
public:
    Component(Graph &graph):G(graph){
        //初始化 
        visited=new bool[G.V()];
        id=new int[G.V()];		 
        ccount=0;
            
        for(int i=0;i<G.V();i++){
            visited[i]=false;
            id[i]=-1;
        }
        
        for(int i=0;i<G.V();i++){ 
            if(!visited[i]){
                dfs(i);			//将与i和i相邻近的节点全都遍历一遍 
                ccount++; 
            }
        } 
    }
    
    ~Component(){
        delete[] visited;
        delete[] id;
    }
    
    int count(){
        return ccount;
    } 
    //检验是否有边 
    bool isConnected(int v,int w){
        assert(v>=0&&v<G.V());
        assert(w>=0&&w<G.V());
        return id[v]==id[w];
    }
};

#endif //INC_05_DFS_AND_COMPONENTS_COMPONENTS_H