#include<bits/stdc++.h>
/*
Created By Tornado2004
*/
using namespace std;
#define debug(x) cout << '[' << #x << " is: " << x << "] " << endl;
#define imod(a , n) (a % n + n ) % n
#define fastio ios_base::sync_with_stdio(false);cin.tie(0);
#define inF freopen("marathon.in","r",stdin );
#define outF freopen("marathon.out" , "w" , stdout ) ;
#define sor(v) sort(v.begin() , v.end());
#define print(v) for(auto f : v ) cout << f << " " ;
#define rsor(v) sort(v.rbegin() , v.rend());
#define rev(v) reverse(v.begin() , v.end());
#define scan(v)for(auto &it : v)cin >> it ;
#define ll long long
#define logar(x , y) log(x) / log(y)
#define int ll
#define pii pair<int , int >
const int N = 1e5 + 5 , K = 11 , M = N * 4 ;
const ll MOD = 1e9 + 7 , oo = 1e9 , OO = 1e18 , mod = MOD ;
const double pi = acos(-1) , eps = 1e-6 ;
//37
// (a ^ b / c ) % mod = (a ^ b ) % MOD * (c ^ (mod - 2)) % mod
// ريتني اعدم المود
int di[] = {0 , 0 , 1 , -1};
int dj[] = {1 , -1 , 0 , 0};
int dis[N];
vector<pair<int , int > > adj[N];
int par[N];
int dijkstra(int s , int e){
memset(dis , '?' , sizeof dis);
dis[s] = 0 ;
priority_queue<pair<int , int > ,vector<pair<int , int > > , greater<pair<int , int > > > q ;
q.push({0 , s});
while(q.size()){
auto tp = q.top();//cout << tp.first << " " << tp.second << endl ;
q.pop();
if(dis[tp.second] < tp.first)continue ;
if(tp.second == e)return tp.first ;
for(auto f : adj[tp.second]){
int nc = tp.first + f.second ;
// debug(f.first);
// debug(nc);
if(dis[f.first] > nc){//cout << "here" << endl ;
par[f.first] = tp.second ;
q.push({nc , f.first});
dis[f.first] = nc ;
}
}
}
}
map<pair<int , int > , int > mp ;
void HappyBirthday(int u){
if(par[u] == -1)return ;
mp[{u , par[u]}] ++ ;
mp[{par[u] , u}] ++ ;
HappyBirthday(par[u]);
}
int32_t main()
{ //inF;
// inF;outF;
fastio;
int n , m;
cin >> n >> m ;
int s , t , u , v ;
cin >> s >> t >> u >> v ;
while(m--){
int a , b , c ;
cin >> a >> b >> c ;
adj[a].push_back({b , c});
adj[b].push_back({a , c});
}
par[s] = -1 ;
dijkstra(s , t);
HappyBirthday(t);
for(int i = 1 ; i <= n ; i++){
for(auto &f : adj[i]){
if(mp.count({i , f.first}))f.second = 0 ;
}
}
cout << dijkstra(u , v);
}
/*🎂🎁🎉👑
HAPPY TORNADO`S BIRTHDAY 💜💜
*/
