#include <bits/stdc++.h>
#define MaxSize 100

/*
* Created by HarvestWu on 2018/07/18.
*/
using namespace std;
typedef int ElemType;

//邊表
typedef struct ArcNode
{
	int adjvex;                 //該邊所指向的結點的位置
	struct ArcNode *nextarc;    //指向下一條邊的指標
	int info;                   //
}ArcNode;

//頂點表
typedef struct
{
	char data;                  //頂點資訊
	ArcNode *firstarc;          //指向第一條邊的指標
}VNode;

//鄰接表
typedef struct
{
	VNode adjlist[MaxSize];
	int n, e;                    //頂點數、邊數
}AGraph;                        //圖的鄰接表型別

//圖的深度優先搜尋遍歷(DFS)
//假設用鄰接表作為圖的儲存結構

int visit[MaxSize];
void DFS(AGraph *G, int v)
{
	ArcNode *p;
	visit[v] = 1;					//置標誌位1代表已訪問
	p = G->adjlist[v].firstarc;		//p指向頂點v的第一條邊
	while (p != NULL)
	{
		if (visit[p->adjvex] == 0)	//未訪問則遞迴訪問
			DFS(G, p->adjvex);
		p = p->nextarc;
	}

}

//圖的廣度優先搜尋遍歷(BFS)
//假設用鄰接表作為圖的儲存結構

void BFS(AGraph *G, int v, int visit[MaxSize])
{
	ArcNode *p;
	int que[MaxSize], front = 0, rear = 0;
	int j;
	visit[v] = 1;				//置標誌位1代表已訪問
	rear = (rear + 1) % MaxSize;
	que[rear] = v;				//當前頂點入隊，便於此層掃描完後，繼續下一層
	while (front != rear)		//隊空則遍歷結束
	{
		front = (front + 1) % MaxSize;
		j = que[front];
		p = G->adjlist[j].firstarc;
		while (p != NULL)
		{
			if (visit[p->adjvex] == 0)
			{
				visit[p->adjvex] = 1;
				rear = (rear + 1) % MaxSize;
				que[rear] = p->adjvex;
			}
			p = p->nextarc;
		}
	}
}

//建立無向圖的鄰接表
void createAGraph2(AGraph *&AG)
{
	int i, j, k;
	ArcNode *q;
	cout << "輸入頂點數、邊數:" << endl;
	cin >> AG->n >> AG->e;
	for (i = 0; i<AG->n; i++)
	{
		AG->adjlist[i].data = i;
		AG->adjlist[i].firstarc = NULL;
	}
	cout << "輸入邊(vi,vj)的頂點序號i,j:" << endl;
	for (k = 0; k<AG->e; ++k)
	{
		cin >> i >> j;
		//頭插法
		q = (ArcNode*)malloc(sizeof(ArcNode));
		q->adjvex = j;
		q->nextarc = AG->adjlist[i].firstarc;
		AG->adjlist[i].firstarc = q;

		q = (ArcNode*)malloc(sizeof(ArcNode));
		q->adjvex = i;
		q->nextarc = AG->adjlist[j].firstarc;
		AG->adjlist[j].firstarc = q;

	}
}

//判斷圖兩頂點間是否有路徑
int trave(AGraph *G,int a,int b)
{
    for(int i=0;i<G->n;++i)
        visit[i]=0;
    //DFS(G,a);//兩種遍歷方式均可
    BFS(G,a,visit);
    if(visit[b]==1)
        return 1;
    else return 0;
}
AGraph *AG;
int main()
{
	AG = (AGraph*)malloc(sizeof(AGraph));
	createAGraph2(AG);
	int a,b;
	cout<<"請輸入頂點a,b："<<endl;
	while(cin>>a>>b)
        cout<<trave(AG,a,b)<<endl;

	return 0;
}