#include <iostream>
#include <queue>
#include <map>
#include <list>
#include <vector>
#include <string>
#include <limits>
#include <cassert>
#include <fstream>
#include <cstring>
#include <bitset>
#include <iomanip>
#include <algorithm>
#include <functional>
#include <cstdio>
#include <ciso646>
#include <array>

using namespace std;

#define FOR(i,a,b) for (int i=(a);i<(b);i++)
#define RFOR(i,a,b) for (int i=(b)-1;i>=(a);i--)
#define REP(i,n) for (int i=0;i<(n);i++)
#define RREP(i,n) for (int i=(n)-1;i>=0;i--)

#define inf 0x3f3f3f3f
#define CLEAR(a) a = decltype(a)()
#define MP make_pair
#define ALL(a) (a).begin(),(a).end()
#define pii pair<int ,int>
#define pcc pair<char,char>
#define pic pair<int,char>
#define pci pair<char,int>
#define VS vector<string>
#define VI vector<int>
#define DEBUG(x) cout<<#x<<": "<<x<<endl
#define pi 2*acos(0.0)
#define INFILE() freopen("in.txt","r",stdin)
#define OUTFILE() freopen("out.txt","w",stdout)
#define ll long long
#define ull unsigned long long
#define eps 1e-14

struct edge {
	int to;
	int c;
	edge(int t_, int c_):to(t_), c(c_){}
	edge():to(0), c(0){}
};

const int MAX_V = 200;

int V;
vector<edge> G[MAX_V];
int d[MAX_V];
int pre[MAX_V];

void dijkstra(int s) {
	priority_queue<pii, vector<pii>, greater<pii> > que;
	memset(d, inf, sizeof(d));
	d[s] = 0;
	que.push(pii(0, s));

	while (not que.empty()) {
		pii p = que.top(); que.pop();
		int v = p.second;
		if (d[v] < p.first) continue;
		for (auto &e : G[v]) {
			if (d[e.to] > d[v] + e.c) {
				d[e.to] = d[v] + e.c;
				pre[e.to] = v;
				que.push(pii(d[e.to], e.to));
			}
			if (d[e.to] == d[v] + e.c) {
				if (v < pre[e.to]) pre[e.to] = v;
			}
		}
	}
}

vector<int> get_path(int s, int t) {
	vector<int> path;
	for (; t != s; t = pre[t]) path.push_back(t);
	return path;
}

int main(void) {
	int N, M, S, Goal; cin >> N >> M >> S >> Goal;
	REP(i, M) {
		int a, b, c; cin >> a >> b >> c;
		G[a].emplace_back(b, c);
		G[b].emplace_back(a, c);
	}

	for (auto &a : G) {
		sort(ALL(a), [](edge left, edge right) {return left.to < right.to; });
	}
	dijkstra(Goal);

	vector<int> v = get_path(Goal, S);
	for (auto &a : v) {
		cout << a << " ";
	}
	cout << Goal << endl;
	cout << endl;
	return 0;
}