#include <bits/stdc++.h>
#pragma optimize("Ofast")
#pragma target("avx2")
using namespace std;
#define ll long long
#define ld long double
#define pb push_back
#define pf push_front
#define pii pair<int,int>
#define all(v) v.begin(),v.end()
#define F first
#define S second
#define mem(a,i) memset(a,i,sizeof(a))
#define sz(s) (int)s.size()
#define y1 yy
#define ppb pop_back
#define lb lower_bound
#define ub upper_bound
#define gcd(a,b) __gcd(a,b)
#define in insert
// #define int ll
const int MAX=5e5+5;
const int block=400;
const ll inf=2e18;
const int mod=998244353;
const int mod1=1e9+9;
const ld eps=1e-9;
int dx[8]={1,0,-1,0,1,-1,-1,1};
int dy[8]={0,1,0,-1,1,-1,1,-1};
int binpow(int a,int n){
if(!n)return 1;
if(n%2==1)return a*binpow(a,n-1)%mod;
int k=binpow(a,n/2);
return k*k%mod;
}
#include "citymapping.h"
vector<int> g[MAX];
int use[MAX];
ll d[MAX];
int ord[MAX];
int n;
bool cmp(int x,int y){
return d[x]<d[y];
}
int s[MAX];
int big[MAX];
void build(int v,int p=-1){
s[v]=1;
big[v]=0;
for(auto to:g[v]){
if(to==p)continue;
build(to,v);
if(s[to]>s[big[v]])big[v]=to;
s[v]+=s[to];
}
}
void find_roads(int N, int Q, int A[], int B[], int W[]) {
n=N;
for(int i=2;i<=n;i++){
ord[i]=i;
d[i]=get_distance(1,i);
}
sort(ord+2,ord+n+1,cmp);
for(int i=2;i<=n;i++){
for(int j=1;j<=n;j++)use[j]=0;
build(1);
int cur=1;
int f=ord[i];
ll d1=d[f];
vector<int> P;
bool was=0;
for(int j=0;j<=10;j++){
vector<int> vec;
int curv=cur;
while(curv){
vec.pb(curv);
curv=big[curv];
}
if(sz(vec)==1){
A[i-2]=vec[0];
B[i-2]=f;
W[i-2]=d1;
g[vec[0]].pb(f);
was=1;
// cout<<i-2<<" "<<vec[0]<<" "<<f<<" "<<d1<<"\n";
break;
}
ll d2=get_distance(vec.back(),f);
ll dpr=(d1+d2-(d[vec.back()]-d[vec[0]]))/2;
for(int i=0;i<sz(vec);i++){
if(d[f]==dpr+d[vec[i]]){
{
bool changed=0;
vector<int> can;
for(auto to:g[vec[i]]){
if(use[to])continue;
if(to!=big[vec[i]]){
can.pb(to);
}
}
if(can.empty())big[vec[i]]=0;
else{
big[vec[i]]=can[0];
}
for(int j=0;j<sz(vec);j++){
if(i!=j)use[vec[j]]=1;
}
}
d1=dpr;
cur=vec[i];
break;
}
}
}
}
return;
}
