#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
typedef long long ll;
#define fi first
#define se second
#define pll pair<ll,ll>
#define pb push_back
#define debug(x) cerr<<#x<<"="<<x<<endl;
#define MP make_pair
#define rep(i,a,b) for(ll i=a;i<b;i++)
#define SZ(x) (ll)x.size()
#define ALL(x) x.begin(),x.end()
#define endl "\n"
const ll inf=1e18;
ll lowbit(ll x){return x&(-x);}
const ll maxn=1e5+5;
map<pll,bool>mp;
vector<pll>alist[maxn];
ll st[maxn],uv[maxn];
ll n,m;
ll s,t;
ll u,v;
void dfs(ll uu){
for(auto x:alist[uu]){
if(st[x.se]>st[uu])continue;
if(st[x.se]+x.fi==st[uu]){
mp[MP(x.se,uu)]=1;
mp[MP(uu,x.se)]=1;
dfs(x.se);
}
}
}
int main(){
ios::sync_with_stdio(0);
cin.tie(0);
ll n,m;cin>>n>>m;
ll s,t;cin>>s>>t;
ll u,v;cin>>u>>v;
rep(i,0,m){
ll a,b,c;cin>>a>>b>>c;
alist[a].pb(MP(c,b));
alist[b].pb(MP(c,a));
}
memset(st,63,sizeof st);
st[s]=0;
priority_queue<pll,vector<pll>,greater<pll>>q;
q.push(MP(0ll,s));
while(!q.empty()){
auto uu=q.top();
q.pop();
if(uu.fi!=st[uu.se])continue;
for(auto x:alist[uu.se]){
if(uu.fi+x.fi<st[x.se]){
st[x.se]=uu.fi+x.fi;
q.push(MP(st[x.se],x.se));
}
}
}
dfs(t);
//for(auto xx:mp)cout<<xx.fi.fi<<" "<<xx.fi.se<<endl;
memset(uv,63,sizeof uv);
uv[u]=0;
while(!q.empty())q.pop();
q.push(MP(0ll,u));
while(!q.empty()){
auto uu=q.top();
q.pop();
if(uu.fi!=uv[uu.se])continue;
for(auto x:alist[uu.se]){
if(mp[MP(x.se,uu.se)])x.fi=0;
//debug(x.fi);
//debug(x.se);
//debug(uu.fi);
if(uu.fi+x.fi<uv[x.se]){
uv[x.se]=uu.fi+x.fi;
q.push(MP(uv[x.se],x.se));
}
}
}
//rep(i,1,n+1)cout<<uv[i]<<" ";
//cout<<endl;
cout<<uv[v]<<endl;
return 0;
}
