#include "swap.h"
#include<bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define all(x) x.begin(),x.end()
#define pii pair<int,int>
#define pb push_back
#define sz(x) (int)(x.size())
#define chmin(x,y) x=min(x,y)
#define chmax(x,y) x=max(x,y)
#define vi vector<int>
#define vp vector<pii>
#define vvi vector<vi>
#define ykh mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count())
#define __lg(x) 63-__builtin_clzll(x)
const int mxn = 3e5 + 5;
int n, m, ty[mxn], cnt, val[mxn], jump[20][mxn], nxt[mxn], dep[mxn];
vector<int>adj[mxn];
struct DSU{
int to[mxn], num[mxn], f[mxn], s[mxn];
void init(){
for(int i = 0; i < mxn; i++){
to[i] = f[i] = s[i] = i;
ty[i] = 0;
num[i] = 1;
}
}
int find(int x){
return x == to[x] ? x : to[x] = find(to[x]);
}
void add(int x, int c, bool t = 1){
cnt++;
adj[cnt].pb(x);
to[x] = cnt;
val[cnt] = c;
ty[cnt] = t;
}
void merge(int x, int y, int c){
int ox = x, oy = y;
x = find(x), y = find(y);
if(x == y){
if(ty[x] == 0){
add(x, c);
}
else{
}
}
else{
if(ty[x] == 0 and ty[y] == 0){
// 鏈
add(x, c);
add(y, c);
cnt++;
adj[cnt].pb(cnt - 1);
adj[cnt].pb(cnt - 2);
val[cnt] = c;
ty[cnt] = 1 - ((ox == f[x] or ox == s[x]) and (oy == f[y] or oy == s[y]));
to[cnt - 1] = cnt;
to[cnt - 2] = cnt;
f[cnt] = f[x] ^ s[x] ^ ox;
s[cnt] = f[y] ^ s[y] ^ oy;
}
else{
cnt++;
ty[cnt] = 1;
val[cnt] = c;
adj[cnt].pb(x);
adj[cnt].pb(y);
to[y] = cnt;
to[x] = cnt;
}
}
}
}d;
void dfs(int v, int pa){
jump[0][v] = pa;
nxt[v] = nxt[pa];
dep[v] = dep[pa] + 1;
if(ty[v] == 1) nxt[v] = v;
for(auto u : adj[v]){
dfs(u, v);
}
}
int lca(int a, int b){
if(dep[a] < dep[b]) swap(a, b);
int dif = dep[a] - dep[b];
for(int i = 19; i >= 0; i--){
if(dif >> i & 1) a = jump[i][a];
}
if(a == b) return nxt[a];
for(int i = 19; i >= 0; i--){
if(jump[i][a] != jump[i][b]){
a = jump[i][a], b = jump[i][b];
}
}
return nxt[jump[0][a]];
}
void init(int N, int M, std::vector<int> U, std::vector<int> V, std::vector<int> W) {
n = N, m = M;
d.init();
vector<array<int, 3>>edges;
for(int i = 0; i < m; i++){
edges.pb({W[i], U[i] + 1, V[i] + 1});
}
sort(all(edges));
cnt = n;
for(auto [c, a, b] : edges){
d.merge(a, b, c);
}
dfs(cnt, cnt);
for(int i = 1; i < 20; i++){
for(int j = 1; j <= cnt; j++){
jump[i][j] = jump[i - 1][jump[i - 1][j]];
}
}
}
int getMinimumFuelCapacity(int X, int Y) {
X++, Y++;
int lc = lca(X, Y);
if(lc == 0) return -1;
else return val[lc];
return 0;
}
