#include <bits/stdc++.h>
using namespace std;


int wf[210][210];
int g[210][210];
int main(){
	for(int i = 0 ; i < 210 ; i++)
		for(int j = 0 ; j < 210 ; j++)
			g[i][j] = wf[i][j] = (i==j?0:1e9);
	
	int N,M,S,G;
	cin >> N >> M >> S >> G;
	for(int i = 0 ; i < M; i++){
		int a,b,c;
		cin >> a >> b >> c;
		wf[a][b] = wf[b][a] = c;
		g[a][b] = g[b][a] = c;
	}
	for(int i = 0 ; i < N ; i++){
		for(int j = 0 ; j < N ; j++){
			for(int k = 0 ; k < N ; k++)
				wf[j][k] = min(wf[j][k],wf[j][i]+wf[i][k]);
		}
	}
	int dist = wf[S][G];
	int cur = S;
	cout << cur;
	while(cur != G){
		for(int i = 0 ; i < N ; i++){
			if( i != cur && wf[cur][G] == g[cur][i] + wf[i][G] ){
				//cout << cur << " " << i << " " << G << endl;
				cur = i;
				break;
			}
		}
		cout << " " << cur;
	}
	cout << endl;
}