#include<iostream>
#include<cstdio>
#include<algorithm>
#include<climits>
#include<string>
#include<vector>
#include<list>
#include<map>
#include<set>
#include<cmath>
#include<queue>
#include<cstring>
#include<stack>
using namespace std;

struct Way{
	int to,cost;
	Way(){}
	Way(int _to,int _cost){
		to=_to; cost=_cost;
	}
};

struct Data{
	int n,cost;
	Data(){}
	Data(int _n,int _cost){
		n=_n; cost=_cost;
	}
	bool operator<(const Data &a)const{
		return cost>a.cost;
	}
};

int N,M,S,G,A,B,C;
vector<Way> way[200];
int memo[200],d[200];

void dfs(int n,vector<int> ans){
    if(memo[n]==true) return;
    memo[n] = true;
    ans.push_back(n);
    if(n==G){
        printf("%d",ans[0]);
        for(int i=1;i<ans.size();i++) printf(" %d",ans[i]); puts("");
    }
    vector<int> way_;
    for(int i=0;i<way[n].size();i++){
        if(d[n]+way[n][i].cost==d[way[n][i].to]){
            way_.push_back(way[n][i].to);
        }
    }
    sort(way_.begin(),way_.end());
    for(int i=0;i<way_.size();i++) dfs(way_[i],ans);
}

int main(){
	cin>>N>>M>>S>>G;
	for(int i=0;i<M;i++){
		cin>>A>>B>>C;
		way[A].push_back(Way(B,C)); way[B].push_back(Way(A,C));
	}

	priority_queue<Data> pq; pq.push(Data(S,0));
	Data pq_c;
    fill_n((int*)d,200,INT_MAX);
	while(!pq.empty()){
		pq_c = pq.top(); pq.pop();
		if(d[pq_c.n]!=INT_MAX) continue;
		d[pq_c.n] = pq_c.cost;
		for(int i=0;i<way[pq_c.n].size();i++){
			pq.push(Data(way[pq_c.n][i].to,pq_c.cost+way[pq_c.n][i].cost));
		}
	}

	vector<int> ans;
	dfs(S,ans);
    return 0;
}