#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
const int maxn = 1e5 + 10;
const int inf = 1e9;
int n, m;
vector<pair<int,ll>> g[maxn];
vector<int> G[maxn];
ll dp[maxn], pd[maxn];
bool mark[maxn];
int Q[maxn], tail, head;
vector<int> builddag(int s, int t){
tail = 0, head = 0;
mark[t] = 1, Q[head ++] = t;
vector<int> ret;
while (tail < head){
int v = Q[tail ++];
ret.push_back(v);
for (auto ed : g[v]){
int u = ed.first, w = ed.second;
if (!mark[u] and dp[u] + w == dp[v])
mark[u] = 1, Q[head ++] = u;
if (dp[u] + w == dp[v])
G[v].push_back(u);
}
}
sort(ret.begin(), ret.end(), [] (int v, int u){ return dp[v] < dp[u];} );
return ret;
}
void dijkstra(int src){
memset(dp, 63, sizeof dp);
dp[src] = 0;
set<pair<ll,int>> s;
s.insert({dp[src], src});
while (!s.empty()){
int v = (*s.begin()).second;
s.erase(s.begin());
for (auto ed : g[v]){
int u = ed.first, w = ed.second;
if (dp[u] > dp[v] + w){
s.erase({dp[u], u});
dp[u] = dp[v] + w;
s.insert({dp[u], u});
}
}
}
}
ll dpfr[maxn], dpto[maxn];
int main(){
ios_base::sync_with_stdio(false);
int m;
int s, t;
int fr, to;
cin >> n >> m >> s >> t >> fr >> to;
for (int i = 0; i < m; i++){
int v, u, c;
cin >> v >> u >> c;
g[v].push_back({u, c});
g[u].push_back({v, c});
}
dijkstra(fr); // keep shortest path data in dp
for (int i = 1; i <= n; i++)
dpfr[i] = dp[i];
dijkstra(to); // keep shortest path data in dp
for (int i = 1; i <= n; i++)
dpto[i] = dp[i];
dijkstra(s); // keep shortest path data in dp
ll answer = dpfr[to];
vector<int> tpl = builddag(s, t); // topological sort of shortest path's DAG s to t
for (int i = 0; i < (int)tpl.size(); i++){
int v = tpl[i];
dp[v] = dpfr[v], pd[v] = dpto[v];
for (auto u : G[v]){
dp[v] = min(dp[v], dp[u]);
pd[v] = min(pd[v], pd[u]);
}
ll now = min(dp[v] + dpto[v], pd[v] + dpfr[v]);
if (answer == -1 or answer > now)
answer = now;
}
cout << answer << '\n';
}
