#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <climits>
#include <cfloat>
#include <map>
#include <utility>
#include <set>
#include <iostream>
#include <memory>
#include <string>
#include <vector>
#include <algorithm>
#include <functional>
#include <sstream>
#include <complex>
#include <stack>
#include <queue>
#include <cstring>

using namespace std;

int main(){
   int N,M,S,G;
   cin >> N >> M >> S >> G;
   vector<pair<int,int> > edge[N];
   int dist[N][N];
   for( int i = 0 ; i <N; i++ )for( int j = 0 ; j <N; j++ ) dist[i][j]=INT_MAX/2;
   for( int i = 0; i < M ; i++ ){
      int a,b,c;
      cin >> a >> b >> c;
      edge[a].push_back(make_pair(b,c));
      edge[b].push_back(make_pair(a,c));
      dist[a][b]=c;
      dist[b][a]=c;
   }
   for( int i = 0 ; i < N; i++ ){
      for( int j = 0 ; j < N ; j++ ){
         for( int k = 0 ; k < N ; k++ ){
            dist[j][k] = min(dist[j][k],dist[j][i]+dist[i][k]);
         }
      }
   }
   for( int i = 0 ; i < N ; i++ ){
      dist[i][i]=0;
      sort(edge[i].begin(),edge[i].end());
   }
   int mindist = dist[S][G];
   vector<int> ans;
   ans.push_back(S);
   int prev = S;
   int curDist =0;
   while( prev!= G){
      for( int i = 0 ; i < (int) edge[prev].size(); i++ ){
         pair<int,int> dw = edge[prev][i];
         //cout << dw.first<<", "<<dw.second<<" "<< mindist<<endl;
         if( curDist + dw.second + dist[dw.first][G] == mindist ){
            //cout << dw.first << endl;
            ans.push_back(dw.first);
            prev = dw.first;
            curDist += dw.second;
            break;
         }
      }
      //cout << endl;
   }
   for( int i = 0 ; i <(int)ans.size(); i++ ){
      cout << ans[i] << " ";
   }
   cout << endl;
   return 0;
}