#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;
int G[200][200];
int pre[200],d[200];
int n;
bool visited[200];
void dijk(int s,int g){
  for(int i=0;i<n;++i) pre[i]=-1,d[i]=1<<25;
  d[s]=0;
  while(true){
    int idx = -1;
    int m = 1<<25;
    for(int i=0;i<n;++i){
      if(m>d[i]&&!visited[i]){
	  m=d[i];
	  idx = i;
      }
    }
    if(idx==-1) break;
    visited[idx]=true;
    for(int i=0;i<n;++i){
      if(d[i]==d[idx]+G[i][idx] && idx<pre[i]) pre[i] = idx;
      if(d[i]>d[idx]+G[i][idx]){
	d[i]=d[idx]+G[i][idx];
	pre[i]=idx;
      }
    }
  }
  
  vector<int> root;
  int node = g;
  while(node!=-1){
    root.push_back(node);
    node = pre[node];
  }
  reverse(root.begin(),root.end());
  for(int i=0,m=root.size();i<m;++i) cout << root[i] << " ";
  cout << endl;
}
int main(){
  int m,s,g;
  cin>>n>>m>>s>>g;
  for(int i=0;i<n;++i) for(int j=0;j<n;++j) G[i][j]=1<<25;
  while(m--){
    int a,b,c;cin>>a>>b>>c;
    G[a][b]=G[b][a]=c;
  }
  dijk(s,g);
  return 0;
}