#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES

#ifdef __unix__
#include <bits/stdc++.h>
#else
#include "bits\stdc++.h"
#endif
#include <vector>
#include <set>
#include <string>
#include <queue>
#define REP(i,a,b) for(i=a;i<b;i++)
#define rep(i,n) REP(i,0,n)
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;

struct Route{
  int next,cost,num;
};

struct long_Route{
  vector<int> route;
  int cost;
};

int N,M,S,G;
vector<Route> st[205];
vector<int> shortest_route;
int min_cost = INT_MAX;

bool isfast(vector<int> v1,vector<int> v2) {
  int i;
  if(v2.size() == 0) return true;
  int min_size = v1.size();
  if(min_size > v2.size()) min_size = v2.size();
  rep(i,min_size) {
    if(v1[i] < v2[i]) return true;
    if(v1[i] > v2[i]) return false;
  }
  return false;
}

void print_v(vector<int> v) {
  int i;
  rep(i,v.size()-1 ) {
    printf("%d ",v[i]);
  }
  
  printf("%d\n",v[i]);
}

void bfs() {
  int test = 1;
  if(test) puts("");
  int i;
  queue<long_Route> qu;
  long_Route start;
  start.route.push_back(S);
  start.cost = 0;
  qu.push(start);
  while( not qu.empty() ) {
    long_Route lR  = qu.front(); qu.pop();
    vector<Route> now_st
      = st[lR.route[lR.route.size()-1]] ;

    rep(i,now_st.size()) {
      Route now_route1 = now_st[i];
      long_Route lR1 = lR;

      if(now_route1.next == G 
        && lR1.cost + lR.cost <= min_cost
        && isfast(lR1.route,shortest_route) ) {
          lR1.route.push_back(now_route1.next);
          shortest_route = lR1.route;
          min_cost = lR1.cost + lR.cost;
      }
      if(lR.route.size() == 1) {
        lR1.route.push_back(now_route1.next);
        lR1.cost = now_route1.cost;
        qu.push(lR1);
      }
      else if(now_route1.cost + lR.cost <= min_cost
        && now_route1.next != lR.route[lR.route.size()-2]) {
          lR1.route.push_back(now_route1.next);
          lR1.cost = now_route1.cost + lR.cost;
          qu.push(lR1);
      }
    }
  }
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  int i,j,k;
  cin >> N >> M >> S >> G;
  rep(i,M) {
    int a,b,c;
    cin >> a >> b >> c;
    Route tmp = {b,c,i};
    st[a].push_back(tmp);
    tmp.next = a; tmp.num = M+i;
    st[b].push_back(tmp);
  }
  bfs();
  print_v(shortest_route);
  return 0;
}