#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <sstream>
#include <cstring>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <numeric>
#include <cctype>
#include <tuple>
#include <array>
#include <climits>
#include <bitset>
#include <cassert>
#include <unordered_map>

#ifdef _MSC_VER
#include <agents.h>
#endif

#define FOR(i, a, b) for(int i = (a); i < (int)(b); ++i)
#define rep(i, n) FOR(i, 0, n)
#define ALL(v) v.begin(), v.end()
#define REV(v) v.rbegin(), v.rend()
#define MEMSET(v, s) memset(v, s, sizeof(v))
#define UNIQUE(v) (v).erase(unique(ALL(v)), (v).end())
#define MP make_pair
#define MT make_tuple

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<int, int> P;

const int N = 202;
int dist[N][N];
int edge[N][N];

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	cout.setf(ios::fixed);
	cout.precision(20);

	int n, m, s, g;
	cin >> n >> m >> s >> g;
	rep(i, n) rep(j, n) dist[i][j] = i == j ? 0 : 1e9;

	rep(i, m){
		int a, b, c;
		cin >> a >> b >> c;
		edge[a][b] = edge[b][a] = c;
		dist[a][b] = dist[b][a] = c;
	}

	rep(i, n) rep(j, n) rep(k, n) dist[j][k] = min(dist[j][k], dist[j][i] + dist[i][k]);

	int pos = s;
	int x = dist[s][g];
	vector<int> ans;
	while (1){
		ans.push_back(pos);
		if (pos == g) break;
		rep(i, n){
			if (edge[pos][i] && edge[pos][i] + dist[i][g] == x){
				x = dist[i][g];
				pos = i;
				break;
			}
		}
	}
	int k = ans.size();
	rep(i, k) cout << ans[i] << " \n"[i == k - 1];
}