#include <iostream>
#include <vector>
#include <climits>
#include <algorithm>
using namespace std;
int N,S,M,G;
vector<vector<int>> vg;
vector<int> vc;
vector<vector<int>> vp;

void exp(int a,int b,vector<int> vh){
  for(int i=0;i<N;++i){
    if(a!=i && vg[a][i]){
      int b2=b+vg[a][i];
      if(b2>vc[i]) continue;
      if(b2<vc[i] && i==G){
        vp.clear();
      }
      vc[i]=b2;
      vector<int> vh2=vh;
      vh2.push_back(i);
      if(i==G){
        vp.push_back(vh2);
      } else {
        exp(i,b2,vh2);
      }
    }
  }
}

int main(){
  cin>>N>>M>>S>>G;
  vg.resize(N);
  for(int i=0;i<N;++i){
    vg[i].resize(N);
  }
  int a,b,c;
  for(int i=0;i<M;++i){
    cin>>a>>b>>c;
    vg[a][b]=c;
    vg[b][a]=c;
  }
  vc.resize(N);
  for(int i=0;i<N;++i){
    vc[i]=INT_MAX;
  }
  vc[S]=0;
  vector<int> vh;
  exp(S,0,vh);
  sort(vp.begin(),vp.end());
  cout<<S;
  for(int i=0;i<vp[0].size();++i){
    cout<<" "<<vp[0][i];
  }
  cout<<endl;
}