#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimize("Ofast,unroll-loops")
using namespace std;
using namespace __gnu_pbds;
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define f first
#define s second
#define int long long
#define pii pair<int,int>
#define ar array
template<class T>bool umax(T &a,T b){if(a<b){a=b;return true;}return false;}
template<class T>bool umin(T &a,T b){if(b<a){a=b;return true;}return false;}
typedef tree<int, null_type, less_equal<int>, rb_tree_tag,
tree_order_statistics_node_update> ordered_set;
const int inf = 1e17 + 7;
const int mod = 1e9 + 7;
const int N = 3e5 + 5;
const int md = 998244353;
int binpow(int a, int b){
if(b == 0)return 1;
if(b % 2 == 0){
int c = binpow(a,b/2);
return (c*c)%mod;
}
return (binpow(a,b-1)*a)%mod;
}
int divi(int a, int b){
return (a*(binpow(b,mod-2)))%mod;
}
int n,m,k;
vector<pii>g[N];
void solve(){
cin >> n >> m;
int a,b,c,d;
cin >> a >> b >> c >> d;
while(m--){
int l,r,x;
cin >> l >> r >> x;
g[l].pb({r,x});
g[r].pb({l,x});
}
priority_queue<pii, vector<pii>,greater<pii>>q;
vector<int>dp(n+1, inf), pr(N);
dp[b] = 0;
q.push({0, b});
while(!q.empty()){
auto x = q.top().s;
auto cost = q.top().f;
q.pop();
if(dp[x] < cost)continue;
for(auto &[to,t]:g[x]){
if(umin(dp[to], cost + t)){
q.push({dp[to], to});
}
}
}
vector<int>dp1(n+1, inf);
dp1[a] = 0;
q.push({0, a});
while(!q.empty()){
auto x = q.top().s;
auto cost = q.top().f;
q.pop();
if(dp1[x] < cost)continue;
for(auto &[to,t]:g[x]){
if(umin(dp1[to], cost + ((dp[x] > dp[to]) ? 0 : t))){
q.push({dp1[to], to});
}
}
}
cout << dp1[d] << "\n";
}
/*
*/
signed main()
{
// freopen("seq.in", "r", stdin);
// freopen("seq.out", "w", stdout);
ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL);
int tt=1;//cin>>tt;
while(tt--)solve();
}
