#include "meetings.h"
#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;
int lca[N][N], used[N], timer, up[N][20], all;
//bitset<N> dk[N], em, cur[18], kek;
vector<int> nh[20], have[N];
inline int get(int a, int b) {
if (a > b) {
swap(a, b);
}
return lca[a][b];
}
inline void update_lca(int a, int b, int c) {
if (a > b) {
swap(a, b);
}
if (lca[a][b] != -1) {
assert(lca[a][b] == c);
}
lca[a][b] = c;
//dk[a][b] = dk[b][a] = 0;
}
vector<pair<int, int>> edge;
void dfs(int root) {
if (SZ(have[root]) == 1) {
return;
}
/*for (int i = 0; i < 18; i++) {
cur[i] = em;
}*/
//shuffle(all(have), rnd);
//vector<vector<int>> nh(1);
//vector<int> up(1);
int id = (have[root][0] == root ? 1 : 0);
int cc = 1;
nh[0] = {have[root][id]};
up[root][0] = have[root][id];
//cur[0][have[0]] = 1;
timer++;
used[have[root][id]] = timer;
for (int i = 1; i < SZ(have[root]); i++) {
if (used[have[root][i]] == timer || have[root][i] == root) {
continue;
}
//cerr << root << ' ' << have[root][i] << '\n';
used[have[root][i]] = timer;
bool ok = false;
/*vector<int> order;
for (int j = 0; j < SZ(nh); j++) {
order.pb(j);
}
shuffle(all(order), rnd);*/
for (int j = 0; j < cc; j++) {
if (ok) {
break;
}
int v;
if (get(up[root][j], have[root][i]) != -1) {
v = get(up[root][j], have[root][i]);
}
else {
v = Query(root, up[root][j], have[root][i]);
all++;
if (all > 1e5) {
exit(0);
}
}
if (v != root) {
/*if (get(up[root][j], have[root][i]) != -1) {
cerr << "CASE 1\n";
}
else {
cerr << "CASE 2\n";
}*/
//cerr << root << ' ' << have[root][i] << ' ' << up[root][j] << ' ' << v << '\n';
if (v == up[root][j]) {
update_lca(v, up[root][j], up[root][j]);
nh[j].pb(have[root][i]);
//cur[j][have[i]] = 1;
ok = true;
break;
}
else {
/*kek = dk[have[i]] & cur[j];
int cnt = kek.count();
for (int iter = 0; iter < cnt; iter++) {
int pos = kek._Find_first();
kek[pos] = 0;
update_lca(pos, have[i], v);
}
kek = dk[v] & cur[j];
cnt = kek.count();
for (int iter = 0; iter < cnt; iter++) {
int pos = kek._Find_first();
kek[pos] = 0;
update_lca(pos, v, v);
}*/
update_lca(have[root][i], v, v);
used[v] = timer;
up[root][j] = v;
nh[j].pb(have[root][i]);
//cur[j][have[i]] = 1;
if (v != have[root][i]) {
nh[j].pb(v);
//cur[j][v] = 1;
}
ok = true;
break;
}
}
}
if (!ok) {
nh[cc] = {have[root][i]};
up[root][cc] = have[root][i];
cc++;
}
}
for (int i = 0; i < cc; i++) {
edge.pb({root, up[root][i]});
}
/*for (auto it : up[root]) {
edge.pb({root, it});
}*/
for (int i = 0; i < cc; i++) {
have[up[root][i]] = nh[i];
}
for (int i = 0; i < cc; i++) {
dfs(up[root][i]);
}
}
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;
//dk[i][j] = dk[j][i] = 1;
}
}
}
int root = rnd() % n;
//cerr << root << '\n';
for (int i = 0; i < n; i++) {
have[root].pb(i);
}
dfs(root);
for (auto &it : edge) {
if (it.F > it.S) {
swap(it.F, it.S);
}
//cerr << it.F << ' ' << it.S << '\n';
Bridge(it.F, it.S);
}
}
