#define _USE_MATH_DEFINES
#include <algorithm>
#include <cstdio>
#include <functional>
#include <iostream>
#include <cfloat>
#include <climits>
#include <cstring>
#include <cmath>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <time.h>
#include <vector>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> i_i;
typedef pair<ll, int> ll_i;
typedef pair<double, int> d_i;
typedef pair<ll, ll> ll_ll;
typedef pair<double, double> d_d;
typedef pair<int, char> i_c;
struct edge { int v, w; };

ll MOD = 1000000007;
ll _MOD = 1000000009;
double EPS = 1e-10;
int INF = INT_MAX / 4;

int main() {
	int N, M, S, G;
	cin >> N >> M >> S >> G;
	vector<vector<int> > d(N, vector<int>(N, INF));
	for (int i = 0; i < N; i++)
		d[i][i] = 0;
	vector<vector<bool> > adj(N, vector<bool>(N));
	while (M--) {
		int a, b, c;
		cin >> a >> b >> c;
		d[a][b] = d[b][a] = c;
		adj[a][b] = adj[b][a] = true;
	}
	for (int k = 0; k < N; k++)
		for (int i = 0; i < N; i++)
			for (int j = 0; j < N; j++)
				d[i][j] = min(d[i][j], d[i][k] + d[k][j]);
	int i = S, mini = d[S][G];
	cout << S;
	while (i != G) {
		for (int j = 0; j < N; j++) {
			if (!adj[i][j] || d[i][j] + d[j][G] > mini) continue;
			cout << ' ' << j;
			mini -= d[i][j];
			i = j;
		}
	}
	cout << endl;
}