// from duckindog wth depression
#include<bits/stdc++.h>
using namespace std;
#define int long long
using pii = pair<int, int>;
const int N = 1e5 + 10;
int n, m;
int s, t, u, v;
vector<pair<int, int>> ad[N];
int f[N], sv[N], trace[N];
void sktra(int x) {
memset(f, 63, sizeof f);
priority_queue<pii, vector<pii>, greater<pii>> q;
q.emplace(f[x] = 0, x);
while (q.size()) {
int dis, u; tie(dis, u) = q.top(); q.pop();
if (dis != f[u]) continue;
for (auto duck : ad[u]) {
int v, w; tie(v, w) = duck;
if (f[v] > dis + w)
q.emplace(f[v] = dis + w, v);
}
}
}
vector<int> node;
bool dd[N];
bool dfs(int a, int pre = 0, int dis = 0) {
if (sv[a] != dis) return 0;
if (a == t || dd[a]) return 1;
bool ret = 0;
for (auto duck : ad[a]) {
int b, c; tie(b, c) = duck;
if (dfs(b, a, dis + c)) {
ret = 1;
if (!dd[a]) node.push_back(a);
dd[a] = 1;
}
}
return ret;
}
int32_t main() {
cin.tie(0)->sync_with_stdio(0);
if (fopen("duck.inp", "r")) {
freopen("duck.inp", "r", stdin);
freopen("duck.out", "w", stdout);
}
cin >> n >> m;
cin >> s >> t >> u >> v;
for (int i = 1; i <= m; ++i) {
int a, b, c; cin >> a >> b >> c;
ad[a].push_back({b, c});
ad[b].push_back({a, c});
}
if (s == u) {
sktra(s);
for (int i = 1; i <= n; ++i) sv[i] = f[i];
dfs(s);
sktra(v);
int dv = dd[v] ? 0 : 1e14;
for (auto x : node) dv = min(dv, f[x]);
cout << dv << '\n';
return 0;
}
}
