#include<stdio.h>
#include<stdlib.h>


int main(void){

  int N,M,S,G;

  scanf("%d %d %d %d",&N,&M,&S,&G);

  int *time,*path;
  time=(int *)malloc(sizeof(int)*N*N);
  path=(int *)malloc(sizeof(int)*N*N);

  int i,j,k;
  for(i=0;i<N;i++){
    for(j=0;j<N;j++){
      time[i*N+j]=(1<<30)/400;
      path[i*N+j]=0;
      if(i==j){
        time[i*N+j]=0;
      }
    }
  }

  for(i=0;i<M;i++){
    int a,b,c;
    scanf("%d %d %d",&a,&b,&c);
    time[a*N+b]=c;
    path[a*N+b]=1;
  }

  for(k=0;k<N;k++){
    for(i=0;i<N;i++){
      for(j=0;j<N;j++){
        if(time[i*N+j]>time[i*N+k]+time[k*N+j]){
          time[i*N+k]=time[i*N+k]+time[k*N+j];
        }
      }
    }
  }

  int now=S;
  while(now!=G){
    printf("%d ",now);
    int next=0;
    while(path[now*N+next]==0){
      next++;
    }
    for(i=next+1;i<N;i++){
      if(path[now*N+i]==1 && time[next*N+G]>time[i*N+G]){
        next=i;
      }
    }
    now=next;
  }
  printf("%d\n",G);
  free(time);
  return 0;
}