#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll inf = 1e17;
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
int n, m; cin >> n >> m;
int s, t, u, v; cin >> s >> t >> u >> v;
vector<pair<int, int>> g[n + 1];
for (int i = 1; i <= m; i++) {
int a, b, c; cin >> a >> b >> c;
g[a].push_back({b, c});
g[b].push_back({a, c});
}
vector<int> path(n + 1, 0);
vector<ll> st(n + 1, inf);
priority_queue<pair<ll, int>, vector<pair<ll, int>>, greater<pair<ll, int>>> pq;
pq.push({0, s});
st[s] = 0;
while (!pq.empty()) {
auto [w, a] = pq.top(); pq.pop();
for (auto [b, c] : g[a]) {
if (1ll * w + c < st[b]) {
st[b] = 1ll * w + c;
pq.push({1ll * w + c, b});
path[b] = a;
}
}
}
map<pair<int, int>, bool> mp;
for (int i = t; path[i]; i = path[i]) {
mp[{i, path[i]}] = 1;
mp[{path[i], i}] = 1;
}
for (int i = 1; i <= n; i++) st[i] = inf;
pq.push({0, u});
st[u] = 0;
while (!pq.empty()) {
auto [w, a] = pq.top(); pq.pop();
for (auto [b, c] : g[a]) {
if (mp[{a, b}] or mp[{b, a}]) c = 0;
if (1ll * w + c < st[b]) {
st[b] = 1ll * w + c;
pq.push({1ll * w + c, b});
}
}
}
cout << st[v] << '\n';
}
