#include<bits/stdc++.h>
#define mp make_pair
using namespace std;
const int N=1e5+10;
bool vs[4*N];
long long dista[N],distb[N],dist[4*N];
vector<pair<long long,int> > adj[4*N];
priority_queue<pair<long long,int>,vector<pair<long long,int> >,greater<pair<long long,int> > > q;
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
int n,m,s,t,st,ed;
cin>>n >>m >>s >>t >>st >>ed;
for(int i=0;i<m;i++){
int a,b;
long long c;
cin>>a >>b >>c;
adj[a].push_back(mp(c,b));
adj[b].push_back(mp(c,a));
adj[3*n+a].push_back(mp(c,3*n+b));
adj[3*n+b].push_back(mp(c,3*n+a));
}
for(int i=1;i<=n;i++) dista[i]=LLONG_MAX,distb[i]=LLONG_MAX;
dista[s]=0,distb[t]=0;
q.push(mp(0,s));
while(!q.empty()){
int u=q.top().second;
q.pop();
if(vs[u]) continue;
vs[u]=true;
for(int i=0;i<adj[u].size();i++){
int v=adj[u][i].second;
long long w=adj[u][i].first;
if(dista[u]+w<dista[v]){
dista[v]=dista[u]+w;
q.push(mp(dista[v],v));
}
}
}
for(int i=1;i<=n;i++) vs[i]=false;
q.push(mp(0,t));
while(!q.empty()){
int u=q.top().second;
q.pop();
if(vs[u]) continue;
vs[u]=true;
for(int i=0;i<adj[u].size();i++){
int v=adj[u][i].second;
long long w=adj[u][i].first;
if(distb[u]+w<distb[v]){
distb[v]=distb[u]+w;
q.push(mp(distb[v],v));
}
}
}
/*for(int i=1;i<=n;i++) cout<<dista[i] <<" ";
cout<<"\n";
for(int i=1;i<=n;i++) cout<<distb[i] <<" ";*/
for(int u=1;u<=n;u++){
adj[u].push_back(mp(0,n+u));
adj[u].push_back(mp(0,2*n+u));
adj[n+u].push_back(mp(0,3*n+u));
adj[2*n+u].push_back(mp(0,3*n+u));
for(int i=0;i<adj[u].size();i++){
int v=adj[u][i].second;
long long w=adj[u][i].first;
if(v>n) continue;
if(dista[u]+w+distb[v]==dista[t]){
adj[n+u].push_back(mp(0,n+v));
adj[2*n+v].push_back(mp(0,2*n+u));
}
}
}
for(int i=1;i<=4*n;i++) dist[i]=LLONG_MAX,vs[i]=false;
dist[st]=0;
q.push(mp(0,st));
while(!q.empty()){
int u=q.top().second;
q.pop();
if(vs[u]) continue;
vs[u]=true;
for(int i=0;i<adj[u].size();i++){
int v=adj[u][i].second;
long long w=adj[u][i].first;
if(dist[u]+w<dist[v]){
dist[v]=dist[u]+w;
q.push(mp(dist[v],v));
}
}
}
cout<<dist[3*n+ed];
/*for(int i=1;i<=4*n;i++){
for(int j=0;j<adj[i].size();j++){
cout<<i <<" " <<adj[i][j].second <<" " <<adj[i][j].first <<"\n";
}
}*/
}
