#include <bits/stdc++.h>
#define ios ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define file(s) if (fopen(s".in", "r")) freopen(s".in", "r", stdin), freopen(s".out", "w", stdout)
#define all(a) a.begin() , a.end()
#define F first
#define S second
using namespace std;
using ll = long long;
const ll N = 2e5+5 , inf = 2e9 + 7;
const ll INF = 1e18 , mod = 1e9+7;
int n , d , t , h[N] , a[N] , b[N];
void init(int N, int D, int H[]) {
n = N; d = D;
for(int i = 0; i < N; i++) h[i] = H[i];
}
multiset<int> st[N];
void curseChanges(int U, int A[], int B[]) {
t = U;
for(int i = 0; i < t; i++){
a[i] = A[i];
b[i] = B[i];
}
map<pair<int,int>,int> mp;
for(int i = 0; i < t; i++){
if(mp[{a[i],b[i]}] == 0){
mp[{a[i],b[i]}] = 1;
mp[{b[i],a[i]}] = 1;
st[a[i]].insert(h[b[i]]);
st[b[i]].insert(h[a[i]]);
} else {
mp[{a[i],b[i]}] = 0;
mp[{b[i],a[i]}] = 0;
st[a[i]].erase(st[a[i]].find(h[b[i]]));
st[b[i]].erase(st[b[i]].find(h[a[i]]));
}
}
}
int question(int x, int y, int v) {
int ans = 1e9;
for(auto z : st[x]){
auto it = st[y].lower_bound(z);
if(it != st[y].end()){
ans = min(ans , abs(*it-z));
// cout << *it <<" " << z << "\n";
}
if(it != st[y].begin()){
it--;
ans = min(ans , abs(*it-z));
// cout << *it <<" " << z << "\n";
}
}
return ans;
}
// int main(){
// int q;
// cin >> n >> d >> t >> q;
// for(int i = 0; i < n; i++) cin >> h[i];
// for(int i = 0; i < t; i++) cin >> a[i] >> b[i];
// while(q--){
// int x , y , v;
// cin >> x >> y >> v;
// cout << question(x,y,v) << "\n";
// }
//
// }
//
