#include "bits/stdc++.h"
using namespace std;
#define print(x) cout<<x<<endl;
#define rep(i,a,b) for(int i=a;i<b;i++)
#define REP(i,a) for(int i=0;i<a;i++)
#define printall(n,array) {for(int i=0;i<n;i++){cout<<array[i]<<" ";}cout<<endl;}
#define U() cout<<endl;
typedef long long ll;
typedef pair<int, int> PI;
typedef pair<int, PI> V;
typedef vector<int> VE;
const ll mod = 1000000007; //10^9+7

int n,m,s,g;
int a[20002];
int b[20002];
int c[20002];

int d[202];
bool used[202];
int cost[202][202];

void dijkstra(int st){
  REP(i,n)d[i]=mod;
  d[st]=0;
  while(true){
    int v=-1;
    REP(u,n){
      if(!used[u]&&(v==-1||d[u]<d[v]))v=u;
    }
    if(v==-1)break;
    used[v]=true;

    REP(u,n){
      d[u]=min(d[u],d[v]+cost[v][u]);
    }
  }
}

VE trace(int st, int go){
  VE ve;
  int now=st;
  while(now!=go){
    REP(i,n){
      if(d[now]-cost[now][i]==d[i]){
        ve.push_back(i);
        now=i;
        break;
      }
    }
  }
  return ve;
}


int main(){
  cin>>n>>m>>s>>g;
  REP(i,202)REP(j,202)cost[i][j]=mod;
  REP(i,m){
    cin>>a[i]>>b[i]>>c[i];
    cost[a[i]][b[i]]=c[i];
    cost[b[i]][a[i]]=c[i];
  }
  dijkstra(g);
  //printall(n,d);///
  //print(d[s]);///
  VE ve=trace(s,g);
  cout<<s<<" ";
  REP(i,ve.size())cout<<ve[i]<<" ";
  U();
}