#include
    
     using namespace std;struct list{    int num;    list *next;    list(){next=NULL;}};list *h,*e,*p;int w[101][101],d[101],n,m;void sou(int u){    int i;    for(i=1;i<=n;i++)    {        if(d[u]+w[u][i]
     
      next=new list;            p=p->next;            p->num=i;        }    }    e=h->next;    delete h;    h=e;    if(h==NULL)        return ;    sou(h->num);}int main(){    int i,j,a,b,c;    while(cin>>n>>m)    {        if(n==0&&m==0)            break;        for(i=0;i<=n;i++)            for(j=0;j<=n;j++)                w[i][j]=0xfffffff;        for(i=0;i
      
       >a>>b>>c;            if(c
       
        num=1;        p=h;        sou(1);        cout<
        
         <