#include"bits/stdc++.h"

//#include<bits/stdc++.h>
using namespace std;
#define print(x) cout<<x<<endl;
#define rep(i,a,b) for(int i=a;i<b;i++)
#define REP(i,a) for(int i=0;i<a;i++)
typedef long long ll;
typedef pair<int, int> PI;
typedef pair<int, PI> V;
typedef vector<int> VE;
const ll mod = 100000000;

int n, m, s, g;
int a[20000], b[20000], c[20000];
int d[202];
bool used[202];
int cost[202][202];
int pr[202];

void dijkstra(int s) {
	REP(i, n)d[i] = mod;
	REP(i, n)used[i] = 0;
	d[s] = 0;

	while (true) {
		int v = -1;
		REP(u, n) {
			if (!used[u] && (v == -1 || d[u] < d[v]))v = u;
		}
		if (v == -1)break;
		used[v] = true;
		REP(u, n) {
			if (d[u] > d[v] + cost[v][u]) {
				d[u] = d[v] + cost[v][u];
				pr[u] = v;
			}
			else if (d[u] == d[v] + cost[v][u]) {
				pr[u] = min(pr[u], v);
			}
		}
	}
}

VE get_path(int t) {
	VE path;
	for (; t != -1; t = pr[t])path.push_back(t);
	reverse(path.begin(), path.end());
	return path;
}

int main() {
	cin >> n >> m >> s >> g;
	REP(i, 202)REP(j, 202)cost[i][j] = mod;
	REP(i, m) {
		cin >> a[i] >> b[i] >> c[i];
		cost[a[i]][b[i]] = c[i];
		cost[b[i]][a[i]] = c[i];
	}
	dijkstra(g);
	//VE v = get_path(s);
	VE v;
	int now = s;
	int i = 0;
	while (now != g) {
		v.push_back(now);
		now = pr[now];
	}
	v.push_back(g);
	//print(d[g]);
	REP(i,v.size())cout<<v[i] << " ";
	cout << endl;
	return 0;
}