#include <bits/stdc++.h>
#define ll long long
#define INF 1000000005
#define MOD 1000000007
#define EPS 1e-10
#define rep(i,n) for(int i=0;i<(int)n;++i)
#define each(a, b) for(auto (a): (b))
#define all(v) (v).begin(),(v).end()
#define fi first
#define se second
#define pb push_back
#define show(x) cout <<#x<<" = "<<(x)<<endl
#define spair(p) cout <<#p<<": "<<p.fi<<" "<<p.se<<endl
#define svec(v) cout<<#v<<":";rep(kbrni,v.size())cout<<" "<<v[kbrni];cout<<endl
#define sset(s) cout<<#s<<":";each(kbrni,s)cout <<" "<<kbrni;cout<<endl

using namespace std;

typedef pair<int,int>P;

const int MAX_N = 201;

struct edge{
	int to;
	int cost;
};

int d[MAX_N];
vector<edge> G[MAX_N];

void dijkstra(int s)
{
	priority_queue<P,vector<P>,greater<P> > que;
	d[s] = 0;
	que.push(P(0,s));
	while(!que.empty()){
		P p = que.top();
		que.pop();
		int v = p.second;
		if(d[v] < p.first) continue;
		vector<edge>::iterator it = G[v].begin();
		rep(i,G[v].size()){
			if(d[G[v][i].to] > d[v] + G[v][i].cost){
				d[G[v][i].to] = d[v] + G[v][i].cost;
				que.push(P(d[G[v][i].to],G[v][i].to));
			}
		}
	}
}

int main()
{
    int n,m,s,g;
    cin >> n >> m >> s >> g;
    rep(i,m){
        int a,b,c;
        cin >> a >> b >> c;
        G[a].pb({b,c});
        G[b].pb({a,c});
    }
    rep(i,n){
        d[i] = INF;
    }
    dijkstra(g);
    int opt = d[s];
    vector<int> route;
    int nw = s;
    route.pb(s);
    int dir = 0;
    while(nw != g){
        vector<P> vec;
        rep(i,G[nw].size()){
            if(dir+G[nw][i].cost == opt - d[G[nw][i].to]){
                vec.pb({G[nw][i].to,G[nw][i].cost});
            }
        }
        sort(all(vec));
        nw = vec[0].fi;
        dir += vec[0].se;
        route.pb(nw);
    }
    int num = (int)route.size();
    rep(i,num-1){
        cout << route[i] << " ";
    }
    cout << route[num-1] << endl;
    return 0;
}