#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <queue>
#include <string>
#include <map>
#include <set>
#include <stack>
#include <tuple>
#include <deque>
#include <array>
#include <numeric>
#include <bitset>
#include <iomanip>
#include <cassert>
#include <chrono>
#include <random>
#include <limits>
#include <iterator>
#include <functional>
#include <sstream>
#include <fstream>
#include <complex>
#include <cstring>
#include <unordered_map>
#include <unordered_set>
using namespace std;

using ll = long long;
constexpr int INF = 1001001001;
// constexpr int mod = 1000000007;
constexpr int mod = 998244353;

template<class T>
inline bool chmax(T& x, T y){
    if(x < y){
        x = y;
        return true;
    }
    return false;
}
template<class T>
inline bool chmin(T& x, T y){
    if(x > y){
        x = y;
        return true;
    }
    return false;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int N, M, S, G;
    cin >> N >> M >> S >> G;
    using edge = pair<int, int>;
    vector<vector<edge>> g(N);
    for(int i = 0; i < M; ++i){
        int a, b, c;
        cin >> a >> b >> c;
        g[a].emplace_back(b, c);
        g[b].emplace_back(a, c);
    }

    vector<int> dist(N, INF), restore(N, N);
    priority_queue<edge, vector<edge>, greater<edge>> que;
    dist[S] = 0;
    que.emplace(0, S);
    while(!que.empty()){
        auto [d, from] = que.top();
        que.pop();
        if(d > dist[from])  continue;
        for(auto [to, cost] : g[from]){
            if(chmin(dist[to], dist[from] + cost)){
                que.emplace(dist[to], to);
                restore[to] = from;
            }
            else if(dist[to] == dist[from] + cost){
                chmin(restore[to], from);
            }
        }
    }

    vector<int> ord;
    while(G != S){
        ord.emplace_back(G);
        G = restore[G];
    }
    ord.emplace_back(S);
    reverse(begin(ord), end(ord));
    int V = ord.size();
    for(int i = 0; i < V; ++i){
        cout << ord[i] << (i == V - 1 ? '\n' : ' ');
    }

    return 0;
}