#include<bits/stdc++.h>
using namespace std;
#define pii pair<int, int>
#define ff first
#define ss second
#define ll long long
#define pll pair<ll, ll>
#define pb push_back
#define int ll
#define mp make_pair
vector<pii> q[200100], dq[200100];
int us[200100], dp[200100], bd[200100], pos[200100], ddp[200100][4], dus[200100][4];
pii d1, d2;
int dfs(int v){
if(v == d1.ss){
bd[v] = 1;
}
pos[v] = 1;
for(pii h: q[v]){
int to = h.ff;
int x = h.ss;
if(dp[to] != dp[v] + x) continue;
if(!pos[to] and dp[to] == dp[v] + x) dfs(to);
bd[v] |= bd[to];
}
return bd[v];
}
void solve(){
int n, m;
cin>>n>>m;
cin>>d1.ff>>d1.ss;
cin>>d2.ff>>d2.ss;
for(int i=1; i<=m; i++){
int l, r, x;
cin>>l>>r>>x;
q[l].pb({r, x});
q[r].pb({l, x});
}
set<pii> d;
d.insert({0, d1.ff});
while(d.size()){
auto it = *d.begin();
int v = it.ss;
if(us[v]){
d.erase(d.find(it));
continue;
}
us[v] = 1;
dp[v] = it.ff;
for(pii h: q[v]){
int to = h.ff;
int x = h.ss;
if(us[to]) continue;
d.insert({dp[v] + x, to});
}
}
dfs(d1.ff);
set<pair<pii, int>> dd;
for(int i=1; i<=n; i++) us[i] = 0;
dd.insert(mp(mp(0, 0), d2.ff));
while(dd.size()){
auto it = *dd.begin();
int v = it.ss;
int f = it.ff.ss;
if(dus[v][f]){
dd.erase(dd.find(it));
continue;
}
//cout<<it.ff.ff<<' '<<it.ff.ss<<' '<<it.ss<<'\n';
dus[v][f] = 1;
ddp[v][f] = it.ff.ff;
if(f == 0){
for(pii h: q[v]){
int to = h.ff;
int x = h.ss;
if(dus[to][1]) continue;
if(bd[v] and bd[to] and dp[to] == dp[v] + x) dd.insert(mp(mp(ddp[v][f], 1), to));
}
for(pii h: q[v]){
int to = h.ff;
int x = h.ss;
if(dus[to][2]) continue;
if(bd[v] and bd[to] and dp[v] == dp[to] + x) dd.insert(mp(mp(ddp[v][f], 2), to));
}
for(pii h: q[v]){
int to = h.ff;
int x = h.ss;
if(dus[to][0]) continue;
dd.insert(mp(mp(ddp[v][f] + x, 0), to));
}
}
if(f == 1){
for(pii h: q[v]){
int to = h.ff;
int x = h.ss;
if(dus[to][1]) continue;
if(bd[v] and bd[to] and dp[to] == dp[v] + x) dd.insert(mp(mp(ddp[v][f], 1), to));
}
for(pii h: q[v]){
int to = h.ff;
int x = h.ss;
if(dus[to][3]) continue;
dd.insert(mp(mp(ddp[v][f] + x, 3), to));
}
}
if(f == 2){
for(pii h: q[v]){
int to = h.ff;
int x = h.ss;
if(dus[to][2]) continue;
if(bd[v] and bd[to] and dp[v] == dp[to] + x) dd.insert(mp(mp(ddp[v][f], 2), to));
}
for(pii h: q[v]){
int to = h.ff;
int x = h.ss;
if(dus[to][3]) continue;
dd.insert(mp(mp(ddp[v][f] + x, 3), to));
}
}
if(f == 3){
for(pii h: q[v]){
int to = h.ff;
int x = h.ss;
if(dus[to][3]) continue;
dd.insert(mp(mp(ddp[v][f] + x, 3), to));
}
}
}
int ans = 1e18;
for(int i=0; i<4; i++){
if(!dus[d2.ss][i]) continue;
ans = min(ans, ddp[d2.ss][i]);
}
cout<<ans<<'\n';
}
signed main(){
solve();
}
