#define here cerr<<"===========================================\n"
#define dbg(x) cerr<<#x<<": "<<x<<endl;
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#define ld double
#define ll int
#define llinf 100000000000000000LL // 10^17
#define pb push_back
#define popb pop_back
#define fi first
#define sc second
#define endl '\n'
#define pll pair<ll,ll>
#define pld pair<ld,ld>
#define sz(a) (ll)(a.size())
#define all(a) a.begin(),a.end()
#define ceri(a,l,r) {cerr<<#a<<": ";for(ll i_ = l;i_<=r;i_++) cerr<<a[i_]<< " ";cerr<<endl;}
#define cer(a) {cerr<<#a<<": ";for(ll x_ : a) cerr<<x_<< " ";cerr<<endl;}
#define daj_mi_malo_vremena ios_base::sync_with_stdio(false);cerr.tie(0);cout.tie(0);cin.tie(0);
using namespace std;
#define maxn 1000005
#define lg 31
ll n,m;
vector<ll> g[maxn];
struct gr{
ll x,y,w;
};
bool cmp(gr a,gr b){return a.w<b.w;}
vector<gr> edge;
ll c[maxn];
bool ok[maxn];
ll dsu[maxn];
ll deg[maxn];
ll in[maxn];
ll out[maxn];
ll it;
ll root(ll x){
while(x!=dsu[x]){
dsu[x] = dsu[dsu[x]];
x = dsu[x];
}
return x;
}
ll st[maxn][lg];
ll oke[maxn][lg];
vector<pll> v;
void upd(ll x,ll y,ll w){
deg[x]++; deg[y]++;
bool f = (deg[x]>=3)||(deg[y]>=3);
x = root(x); y = root(y);
++it;
if(x==y){
g[x].pb(it);
g[it].pb(x);
v.pb({it,x});
ok[it] = 1;
dsu[x] = it;
}else{
g[x].pb(it);
g[it].pb(x);
g[y].pb(it);
g[it].pb(y);
v.pb({it,x});
v.pb({it,y});
ok[it] = ok[x]|ok[y]|f;
dsu[x] = dsu[y] = it;
}
c[it] = w;
}
ll itr = 0;
void dfs(ll u,ll p){
st[u][0] = p;
oke[u][0] = ok[p];
in[u] = ++itr;
for(ll s : g[u]){
if(s==p) continue;
dfs(s,u);
}
out[u] = itr;
}
bool intree(ll x,ll y){
return in[y]<=in[x]&&out[x]<=out[y];
}
ll lca(ll x,ll y){
if(intree(y,x)) return x;
if(intree(x,y)) return y;
for(ll j = lg-1;j>=0;j--){
if(!intree(x,st[y][j])) y = st[y][j];
}
return st[y][0];
}
void init(int N, int M, vector<int> U, vector<int> V, vector<int> W) {
n = N; m = M;
it = n;
iota(dsu+1,dsu+maxn,1);
for(ll i = 0;i<m;i++){
ll x = U[i]; ll y = V[i]; ll w = W[i];
++x; ++y;
edge.pb({x,y,w});
}
sort(all(edge),cmp);
for(gr e : edge){
ll x = e.x; ll y = e.y; ll w = e.w;
upd(x,y,w);
}
dfs(it,it);
for(ll j = 1;j<lg;j++){
for(ll i = 1;i<=it;i++) st[i][j] = st[st[i][j-1]][j-1];
}
for(ll j = 1;j<lg;j++){
for(ll i = 1;i<=it;i++) oke[i][j] = oke[i][j-1]|oke[st[i][j-1]][j-1];
}
}
int getMinimumFuelCapacity(int X, int Y) {
ll x = X; ll y = Y;
++x; ++y;
ll z = lca(x,y);
if(ok[z]) return c[z];
for(ll j = lg-1;j>=0;j--){
if(!oke[z][j]) z = st[z][j];
}
z = st[z][0];
ll ans = c[z];
if(ok[z]==0) ans = -1;
return ans;
}
/*
5 6
0 1 4
0 2 4
1 2 1
1 3 2
1 4 10
2 3 3
3
1 2
2 4
0 1
*/
