#include <cstdio>
#include <cstring>
#include <iostream>
#include <string>
#include <cmath>
#include <bitset>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <algorithm>
#include <complex>
#include <unordered_map>
#include <unordered_set>
#include <random>
#include <cassert>
using namespace std;
typedef long long int ll;
typedef pair<int, int> P;
const int INF=1e9;
int main()
{
	int n, m, s, t;
	cin>>n>>m>>s>>t;
	vector<P> g[201];
	for(int i=0; i<m; i++){
		int a, b, c;
		cin>>a>>b>>c;
		g[a].push_back(P(b, c)); g[b].push_back(P(a, c));
	}
	for(int i=0; i<n; i++) sort(g[i].begin(), g[i].end());
	priority_queue<P, vector<P>, greater<P>> que;
	que.push(P(0, t));
	int d[201]; fill(d, d+n, INF);
	d[t]=0;
	while(!que.empty()){
		P p=que.top(); que.pop();
		int x=p.second;
		if(p.first>d[x]) continue;
		for(auto q:g[x]){
			int y=q.first;
			if(d[y]>d[x]+q.second){
				d[y]=d[x]+q.second;
				que.push(P(d[y], y));
			}
		}
	}
	vector<int> ans; ans.push_back(s);
	while(ans.back()!=t){
		int x=ans.back();
		for(auto p:g[x]){
			int y=p.first;
			if(d[x]==d[y]+p.second){
				ans.push_back(y);
				break;
			}
		}
	}
	for(int i=0; i<ans.size(); i++){
		cout<<ans[i];
		if(i<ans.size()-1) cout<<" ";
	}
	cout<<endl;
	return 0;
}