#include <bits/stdc++.h>

using namespace std;

#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()

template<typename A, typename B> inline bool chmax(A &a, B b) { if (a<b) { a=b; return 1; } return 0; }
template<typename A, typename B> inline bool chmin(A &a, B b) { if (a>b) { a=b; return 1; } return 0; }

typedef unsigned long long ull;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<pii, pii> P;

const ll INF = 1ll<<29;
const ll MOD = 1000000007;
const double EPS  = 1e-10;

int n, m, st, gr;
int d[200][200];
vector<pii> g[200];

int main() {
	cin >> n >> m >> st >> gr;
	
	fill(d[0], d[n], INF);
	REP(i, m) {
		int a, b, c;
		scanf("%d %d %d", &a, &b, &c);
		d[a][b] = c;
		d[b][a] = c;
		g[a].push_back(pii(b, c));
		g[b].push_back(pii(a, c));
	}
	REP(i, n) d[i][i] = 0;
	
	REP(k, n) REP(i, n) REP(j, n) chmin(d[i][j], d[i][k] + d[k][j]);
	
	REP(i, n) sort(ALL(g[i]));
	
	vector<int> ans;
	ans.push_back(st);
	
	while (ans.back() != gr) {
		int u = ans.back();
		
		REP(i, g[u].size()) {
			int v = g[u][i].first;
			
			if (d[st][u] + g[u][i].second + d[v][gr] == d[st][gr]) {
				ans.push_back(v);
				break;
			}
		}
	}
	
	REP(i, ans.size()) printf("%d%c", ans[i], i == ans.size() - 1 ? '\n' : ' ');
	
	return 0;
}