#include <bits/stdc++.h>
#define EPS 1e-9
#define INF 1070000000LL
#define MOD 1000000007LL
#define fir first
#define foreach(it,X) for(auto it=(X).begin();it!=(X).end();it++)
#define numa(x,a) for(auto x: a)
#define ite iterator
#define mp make_pair
#define rep(i,n) rep2(i,0,n)
#define rep2(i,m,n) for(int i=m;i<(n);i++)
#define pb push_back
#define pf push_front
#define sec second
#define sz(x) ((int)(x).size())
#define ALL( c ) (c).begin(), (c).end()
#define gcd(a,b) __gcd(a,b)
#define mem(x,n) memset(x,n,sizeof(x))
#define endl "\n"
using namespace std;
template <int POS, class TUPLE> void deploy(std::ostream &os, const TUPLE &tuple){}
template <int POS, class TUPLE, class H, class ...Ts> void deploy(std::ostream &os, const TUPLE &t){ os << (POS == 0 ? "" : ", ") << get<POS>(t); deploy<POS + 1, TUPLE, Ts...>(os, t); }
template <class T,class U> std::ostream& operator<<(std::ostream &os, std::pair<T,U> &p){ os << "(" << p.first <<", " << p.second <<")";return os; }
template <class T> std::ostream& operator<<(std::ostream &os, std::vector<T> &v){ int remain = v.size(); os << "{"; for(auto e: v) os << e << (--remain == 0 ? "}" : ", "); return os; }
template <class T> std::ostream& operator<<(std::ostream &os, std::set<T> &v){ int remain = v.size(); os << "{"; for(auto e: v) os << e << (--remain == 0 ? "}" : ", "); return os; }
template <class T, class K> std::ostream& operator<<(std::ostream &os, std::map<T, K> &mp){ int remain = mp.size(); os << "{"; for(auto e: mp) os << "(" << e.first << " -> " << e.second << ")" << (--remain == 0 ? "}" : ", "); return os; }
#define DEBUG1(var0) { std::cerr << (#var0) << "=" << (var0) << endl; }
#define DEBUG2(var0, var1) { std::cerr << (#var0) << "=" << (var0) << ", ";DEBUG1(var1); }
#define DEBUG3(var0, var1, var2) { std::cerr << (#var0) << "=" << (var0) << ", ";DEBUG2(var1,var2); }
#define DEBUG4(var0, var1, var2, var3) { std::cerr << (#var0) << "=" << (var0) << ", ";DEBUG3(var1,var2,var3); }
using ll = long long;
using PLI = pair <ll,int>;
int N,M,S,G;
vector <pair <int,int> > edge[300];
ll cost[300];
int pass[300];
int main()
{
  cin.tie(0);
  ios_base::sync_with_stdio(0);
  cin >> N >> M >> S >> G;
  rep(i,M){
    int a,b,c;
    cin >> a >> b >> c;
    edge[a].pb(mp(b,c));
    edge[b].pb(mp(a,c));
  }
  rep(i,N){
    cost[i] = INF;
    pass[i] = INF;
  }
  priority_queue <PLI,vector <PLI>,greater <PLI>> que;
  cost[S] = 0;
  que.push(mp(0,S));
  while(!que.empty()){
    auto t = que.top();
    que.pop();
    auto c = t.fir;
    auto now = t.sec;
    numa(x,edge[now]){
      auto next = x.fir;
      auto pc = x.sec;
      if (c + pc < cost[next]) {
        pass[next] = now;
        cost[next] = c+pc;
        que.push(mp(c+pc,next));
      }else if (c+pc == cost[next] && pass[next] > now){
        pass[next] = now;
      }
    }
  }
  {
    int now = G;
    vector <int> ans;
    ans.pb(now);
    while(now != S){
      now = pass[now];
      ans.pb(now);
    }
    reverse(ALL(ans));
    rep(i,sz(ans)){
      if (i) {
        cout << " ";
      }
      cout << ans[i];
    }
    cout << endl;
  }
  return 0;
}