#include <iostream>
#include <vector>
#include <utility>
#include <queue>
using namespace std;
enum EdgeState{
NORMAL,
DIJKSTRA,
DONE
};
vector<vector<pair<int, int>>> graph;
vector<vector<EdgeState>> states;
vector<int> times;
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n, m, s, t, u, v;
cin>>n>>m>>s>>t>>u>>v;
graph.resize(n+7);
states.resize(n+7);
times.resize(n+7, -1);
for (int i=0;i<m;i++){
int v1, v2, w;
cin>>v1>>v2>>w;
graph[v1].push_back({v2, w});
graph[v2].push_back({v1, w});
states[v1].push_back(NORMAL);
states[v2].push_back(NORMAL);
}
priority_queue<pair<int, pair<int, int>>, vector<pair<int, pair<int, int>>>, greater<pair<int, pair<int, int>>>> dijkstrapq;
dijkstrapq.push({0, {s, 0}});
while (!dijkstrapq.empty()){
pair<int, pair<int, int>> p=dijkstrapq.top();
dijkstrapq.pop();
if (times[p.second.first]!=-1) continue;
for (int i=0;i<graph[p.second.first].size();i++){
if (graph[p.second.first][i].first==p.second.second){
states[p.second.first][i]=DIJKSTRA;
}
}
if (p.second.first==t) break;
times[p.second.first]=p.first;
for (int i=0;i<graph[p.second.first].size();i++){
if (times[graph[p.second.first][i].first]==-1||times[graph[p.second.first][i].first]==p.first+graph[p.second.first][i].second){
dijkstrapq.push({p.first+graph[p.second.first][i].second, {graph[p.second.first][i].first, p.second.first}});
}
}
}
/*for (int i=1;i<=n;i++){
for (int j=0;j<graph[i].size();j++){
cout<<graph[i][j].first<<" "<<(states[i][j]==DIJKSTRA?"DIJKSTRA ":"");
}
cout<<'\n';
}*/
queue<int> bfsq;
bfsq.push(t);
while (!bfsq.empty()){
int ve=bfsq.front();
bfsq.pop();
for (int i=0;i<graph[ve].size();i++){
if (states[ve][i]!=DIJKSTRA) continue;
states[ve][i]=DONE;
for (int j=0;j<graph[graph[ve][i].first].size();j++){
if (graph[graph[ve][i].first][j].first==ve){
states[graph[ve][i].first][j]=DONE;
}
}
bfsq.push(graph[ve][i].first);
}
}
/*for (int i=1;i<=n;i++){
for (int j=0;j<graph[i].size();j++){
cout<<graph[i][j].first<<" "<<(states[i][j]==DONE?"DONE ":"");
}
cout<<'\n';
}*/
for (int i=0;i<times.size();i++) times[i]=0;
while (!dijkstrapq.empty()) dijkstrapq.pop();
dijkstrapq.push({0, {v, 0}});
while (!dijkstrapq.empty()){
pair<int, pair<int, int>> p=dijkstrapq.top();
dijkstrapq.pop();
times[p.second.first]=1;
for (int i=0;i<graph[p.second.first].size();i++){
if (states[p.second.first][i]==DONE){
cout<<p.first<<'\n';
return 0;
}
if (times[graph[p.second.first][i].first]==0){
dijkstrapq.push({p.first+graph[p.second.first][i].second, {graph[p.second.first][i].first, 0}});
}
}
}
return 0;
}
