#include <bits/stdc++.h>
using namespace std;

#define _p(...) (void)printf(__VA_ARGS__)
#define forr(x,arr) for(auto&& x:arr)
#define _overload3(_1,_2,_3,name,...) name
#define _rep2(i,n) _rep3(i,0,n)
#define _rep3(i,a,b) for(int i=int(a);i<int(b);++i)
#define rep(...) _overload3(__VA_ARGS__,_rep3,_rep2,)(__VA_ARGS__)
#define _rrep2(i,n) _rrep3(i,0,n)
#define _rrep3(i,a,b) for(int i=int(b)-1;i>=int(a);i--)
#define rrep(...) _overload3(__VA_ARGS__,_rrep3,_rrep2,)(__VA_ARGS__)
#define ALL(x) (x).begin(), (x).end()
#define BIT(n) (1LL<<(n))
#define SZ(x) ((int)(x).size())
#define fst first
#define snd second
typedef vector<int> vi;typedef vector<vi> vvi;typedef pair<int,int> pii;typedef vector<pii> vpii;
typedef long long ll;

vector<pair<int, int>> E[200];
int D[200];

void dijkstra(int s, int g) {
  priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>> > q;
  D[s] = 0;
  q.push({0, s});

  while (!q.empty()) {
    int c = q.top().first;
    int v = q.top().second;
    q.pop();
    if (v == g) return;
    if (D[v] < c) continue;
    for (auto&& nex : E[v]) {
      int nv = nex.first;
      int nc = c + nex.second;
      if (D[nv] > nc) {
        D[nv] = nc;
        q.push({nc, nv});
      }
    }
  }
}

void Main() {
  int N, M, S, G;
  scanf("%d%d%d%d", &N, &M, &S, &G);
  rep(i, M) {
    int u, v, w;
    scanf("%d%d%d", &u, &v, &w);
    E[u].push_back({v, w});
    E[v].push_back({u, w});
  }
  memset(D, 0x3f, sizeof(D));

  dijkstra(G, S);
  int p = S;
  vi ans;
  while (p != G) {
    ans.push_back(p);
    int mi = 1e9;
    forr(nex, E[p]) if (D[nex.first] + nex.second == D[p]) {
      mi = min(mi, nex.first);
    }
    p = mi;
  }
  ans.push_back(G);
  rep(i, SZ(ans)) {
    _p(i+1<SZ(ans)?"%d ":"%d\n", ans[i]);
  }
}
int main() { cin.tie(0); ios::sync_with_stdio(false); Main(); return 0; }