#include "meetings.h"
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("no-stack-protector")
//#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
typedef long long ll;
typedef long double ld;
using namespace std;
#define F first
#define S second
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define SZ(x) (int)(x).size()
mt19937 rnd(228);
const int N = 2010;
short lca[N][N], used[N], timer, up[N][20], all;
short nh[20][N], have[N][N], sz_nh[20], sz_have[N];
bool was[N];
inline short get(short a, short b) {
if (a > b) {
swap(a, b);
}
return lca[a][b];
}
inline void update_lca(short a, short b, short c) {
if (a > b) {
swap(a, b);
}
lca[a][b] = c;
}
vector<pair<int, int>> edge;
void Solve(int n) {
/*for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
if (i == j) {
lca[i][j] = i;
}
else {
lca[i][j] = -1;
}
}
}*/
short root = rnd() % n;
for (int i = 0; i < n; i++) {
have[root][sz_have[root]++] = i;
}
queue<short> q;
q.push(root);
while (!q.empty()) {
int root = q.front();
assert(!was[root]);
was[root] = true;
q.pop();
if (sz_have[root] == 1) {
continue;
}
shuffle(have[root], have[root] + sz_have[root], rnd);
short id = (have[root][0] == root ? 1 : 0);
short cc = 1;
nh[0][0] = have[root][id];
sz_nh[0] = 1;
up[root][0] = have[root][id];
timer++;
used[have[root][id]] = timer;
vector<short> order;
/*for (int i = 0; i < 18; i++) {
order.pb(i);
}
shuffle(all(order), rnd);*/
for (int i = 1; i < sz_have[root]; i++) {
if (used[have[root][i]] == timer || have[root][i] == root) {
continue;
}
used[have[root][i]] = timer;
bool ok = false;
for (int j = 0; j < cc; j++) {
short v;
/*if (get(up[root][j], have[root][i]) != -1) {
v = get(up[root][j], have[root][i]);
}
else {*/
v = (up[root][j] == have[root][i] ? have[root][i] : Query(root, up[root][j], have[root][i]));
//}
if (v != root) {
/*if (v == up[root][j]) {
//update_lca(v, up[root][j], up[root][j]);
nh[j][sz_nh[j]] = have[root][i];
sz_nh[j]++;
ok = true;
break;
}
else {
//update_lca(have[root][i], v, v);
used[v] = timer;
up[root][j] = v;
nh[j][sz_nh[j]] = have[root][i];
sz_nh[j]++;
if (v != have[root][i]) {
nh[j][sz_nh[j]] = v;
sz_nh[j]++;
}
ok = true;
break;
}*/
up[root][j] = v;
nh[j][sz_nh[j]] = have[root][i];
sz_nh[j]++;
ok = true;
break;
}
}
if (!ok) {
nh[cc][0] = have[root][i];
sz_nh[cc] = 1;
up[root][cc] = have[root][i];
cc++;
}
}
for (int i = 0; i < cc; i++) {
edge.pb({root, up[root][i]});
}
for (int i = 0; i < cc; i++) {
for (int j = 0; j < sz_nh[i]; j++) {
have[up[root][i]][j] = nh[i][j];
}
sz_have[up[root][i]] = sz_nh[i];
}
for (int i = 0; i < cc; i++) {
q.push(up[root][i]);
}
}
for (auto &it : edge) {
if (it.F > it.S) {
swap(it.F, it.S);
}
Bridge(it.F, it.S);
}
}
