无向图（广搜）

#include<stdio.h>
int main()
{
	int i,j,m,n,a,b,cur,book[101]={0},e[101][101];
	int que[10001],head,tail;
	scanf("%d %d",&n,&m);
	for(i=1;i<=n;i++)
	    for(j=1;j<=n;j++)
	       if(i==j) e[i][j]=0;
	       else e[i][j]=9999999;
	       
	for(i=1;i<=m;i++)
	{
		scanf("%d %d",&a,&b);
		e[a][b]=1;
		e[b][a]=1;
	} 
    head=1;
	tail=1;
	
	que[tail]=1;
	tail++;
	book[1]=1;
	
	while(head<tail)
	{
		cur=que[head];
		for(i=1;i<=n;i++)
		{
			if(e[cur][i]==1&&book[i]==0)
			{
				que[tail]=i;
				tail++;
				book[i]=1;
			}
			if(tail>n)
			{
				break;
			}
		}
		head++;
	}
	for(i=1;i<tail;i++)
	    printf("%d ",que[i]);
	return 0;
 }