#include <bits/stdc++.h>

#define _overload(_1,_2,_3,name,...) name
#define _rep(i,n) _range(i,0,n)
#define _range(i,a,b) for(int i=int(a);i<int(b);++i)
#define rep(...) _overload(__VA_ARGS__,_range,_rep,)(__VA_ARGS__)

#define _rrep(i,n) _rrange(i,n,0)
#define _rrange(i,a,b) for(int i=int(a)-1;i>=int(b);--i)
#define rrep(...) _overload(__VA_ARGS__,_rrange,_rrep,)(__VA_ARGS__)

#define _all(arg) begin(arg),end(arg)
#define uniq(arg) sort(_all(arg)),(arg).erase(unique(_all(arg)),end(arg))
#define getidx(ary,key) lower_bound(_all(ary),key)-begin(ary)
#define clr(a,b) memset((a),(b),sizeof(a))
#define bit(n) (1LL<<(n))
#define popcount(n) (__builtin_popcountll(n))

template<class T>bool chmax(T &a, const T &b) { return (a<b)?(a=b,1):0;}
template<class T>bool chmin(T &a, const T &b) { return (b<a)?(a=b,1):0;}

using namespace std;

const int dx[8]={1,0,-1,0,1,-1,-1,1};
const int dy[8]={0,1,0,-1,1,1,-1,-1};
const int inf=1<<28;


int main(void){
	int n,m,s,g;
	cin >> n >> m >> s >> g;


	vector<int> graph[210];
	int edge[210][210],dist[210][210];

	rep(i,n)rep(j,n) edge[i][j]=dist[i][j]=(i==j)?0:inf;

	rep(i,m){
		int a,b,c;
		cin >> a >> b >> c;
		edge[a][b]=edge[b][a]=c;
		dist[a][b]=dist[b][a]=c;
		graph[a].push_back(b);
		graph[b].push_back(a);
	}

	rep(k,n)rep(i,n)rep(j,n) chmin(dist[i][j],dist[i][k]+dist[k][j]);

	vector<int> ans={s};

	int cur=s;
	while(cur!=g){
		sort(_all(graph[cur]));
		for(auto &nxt:graph[cur]){
			if(dist[s][cur]+edge[cur][nxt]+dist[nxt][g]==dist[s][g]){
				ans.push_back(nxt);
				cur=nxt;
				break;
			}
		}
	}


	rep(i,ans.size()) cout << (i?" ":"") << ans[i];
	cout << endl;
	return 0;
}