#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll INF = 1e18;
int n, m, S, T, U, V;
vector<array<int, 2>> v[100100];
ll d[100100];
bool chk[100100];
priority_queue<array<ll, 2>> pq;
ll d2[100100][4];
priority_queue<array<ll, 3>> pq2;
void dfs(int u) {
assert(!chk[u]);
chk[u] = 1;
for(auto [x, y] : v[u]) if(d[u]-y == d[x]) dfs(x);
}
int main(){
cin.tie(0)->sync_with_stdio(0);
cin >> n >> m >> S >> T >> U >> V;
for(int i=1;i<=m;i++) {
int a, b, c; cin >> a >> b >> c;
v[a].push_back({b, c}), v[b].push_back({a, c});
}
fill(d+1, d+1+n, INF);
d[S] = 0, pq.push({0, S});
while(!pq.empty()) {
auto [c, u] = pq.top(); pq.pop();
if(-c > d[u]) continue;
for(auto [x, y] : v[u]) if(y-c < d[x]) d[x] = y-c, pq.push({c-y, x});
}
dfs(T);
for(int i=1;i<=n;i++) d2[i][0] = d2[i][1] = d2[i][2] = d2[i][3] = INF;
d2[U][0] = 0, pq2.push({0, U, 0});
while(!pq2.empty()) {
auto [c, u, t] = pq2.top(); pq2.pop();
if(-c > d2[u][t]) continue;
if(u == V) return cout << -c, 0;
if(t < 3 && chk[u]) for(auto [x, y] : v[u]) if(chk[x] && abs(d[x]-d[u]) == y){
if(t == 1 && d[x] > d[u]) continue;
if(t == 2 && d[x] < d[u]) continue;
ll T = d[x] > d[u] ? 2 : 1;
if(-c < d2[x][T]) d2[x][T] = -c, pq2.push({c, x, T});
}
for(auto [x, y] : v[u]) {
ll D = y-c, T = t ? 3 : 0;
if(D < d2[x][T]) d2[x][T] = D, pq2.push({-D, x, T});
}
}
}
