#include <bits/stdc++.h>
using namespace std;
typedef long long LL;
const LL MOD = 1000000007;
#define pb push_back
#define all(c) (c).begin(), (c).end()
#define debug(x) cout << #x << " : " << x << endl
#define part cout << "----------------------------------\n";
#include <iostream>
int dx[] = {1, 1, 0, -1, -1, -1, 0, 1}; // trick to explore an implicit 2D grid
int dy[] = {0, 1, 1, 1, 0, -1, -1, -1}; // S,SE,E,NE,N,NW,W,SW neighbors //GO FOR EVEN FOR 4 moves
char ch[] = {'U', '!', 'L', '!', 'D', '!', 'R', '!'};
#define fastinput \
ios_base::sync_with_stdio(false); \
cin.tie(NULL); \
cout.tie(NULL);
const int M = 1e5 + 1;
vector<pair<LL, int>> adj[M];
LL n;
const LL INF = LONG_LONG_MAX;
vector<LL> d_algo(int src)
{
vector<LL> dis(n + 1, INF);
vector<bool> processed(n + 1, false);
using T = pair<LL, int>;
priority_queue<T, vector<T>, greater<>> q;
dis[src] = 0;
q.push({0, src});
while (!q.empty())
{
auto ptr = q.top();
LL node, dis_now;
tie(dis_now, node) = ptr;
q.pop();
if (processed[node])
{
continue;
}
processed[node] = true;
for (const auto &x : adj[node])
{
int c = x.first;
LL wt = x.second;
LL poss = wt + dis_now;
if (poss < dis[c])
{
dis[c] = poss;
q.push({dis[c], c});
}
}
}
return dis;
}
int main()
{
fastinput;
LL m, i, j, tc, k;
//messi
cin >> n >> m;
LL src1, src2, dest1, dest2;
cin >> src1 >> dest1;
cin >> src2 >> dest2;
while (m--)
{
cin >> i >> j >> k;
adj[i].pb({j, k});
swap(i, j);
adj[i].pb({j, k});
}
vector<LL> dis1 = d_algo(src1);
vector<LL> dis2 = d_algo(dest1);
///////////////////////////////////////
int src = src2;
vector<LL> dis(n + 1, INF);
vector<bool> processed(n + 1, false);
using T = pair<LL, int>;
priority_queue<T, vector<T>, greater<>> q;
dis[src] = 0;
q.push({0, src});
auto nice = [&](int n1, int n2, LL wt)
{
if (dis1[n1] + dis2[n2] + wt == dis1[dest1])
{
return true;
}
swap(n1, n2);
if (dis1[n1] + dis2[n2] + wt == dis1[dest1])
{
return true;
}
return false;
};
while (!q.empty())
{
auto ptr = q.top();
LL node, dis_now;
tie(dis_now, node) = ptr;
q.pop();
if (processed[node])
{
continue;
}
processed[node] = true;
for (const auto &x : adj[node])
{
int c = x.first;
LL wt = x.second;
if (nice(node, c, wt))
{
wt = 0;
}
LL poss = wt + dis_now;
if (poss < dis[c])
{
dis[c] = poss;
q.push({dis[c], c});
}
}
}
/////////////////////////////////////////
// debug(dis[dest2]);
// for (i = 1; i <= n; i++)
// {
// cout << "dis " << i << " = " << dis[i] << endl;
// }
cout << dis[dest2] << endl;
return 0;
}
