#include "meetings.h"
#include <bits/stdc++.h>
using namespace std;
int global_A;
int n;
vector< pair<int, int> > sol;
inline void add_edge(int a, int b) {
sol.push_back(make_pair(a, b));
}
bool cmp(int a, int b) {
if (a == b) return false;
return Query(global_A, a, b) == a;
}
void solve(vector<int> nodes) {
if (nodes.size() == 1) return;
if (nodes.size() == 2) {
add_edge(nodes[0], nodes[1]);
return;
}
int n = nodes.size();
int A = nodes[rand() % n];
int B;
do {
B = nodes[rand() % n];
} while (A == B);
vector<int> path;
vector<int> query_ans(n);
for (int i = 0; i < n; ++i)
if (nodes[i] != A && nodes[i] != B) {
query_ans[i] = Query(A, B, nodes[i]);
if (query_ans[i] == nodes[i])
path.push_back(nodes[i]);
} else {
if (nodes[i] == A) query_ans[i] = A;
if (nodes[i] == B) query_ans[i] = B;
}
global_A = A;
sort(path.begin(), path.end(), cmp);
path.insert(path.begin(), A);
path.push_back(B);
for (size_t i = 0; i + 1 < path.size(); ++i)
add_edge(path[i], path[i + 1]);
vector< vector<int> > groups(path.size());
for (int i = 0; i < n; ++i) {
for (size_t j = 0; j < path.size(); ++j)
if (path[j] == query_ans[i]) {
groups[j].push_back(nodes[i]);
break;
}
}
for(auto it : groups)
solve(it);
}
void print_tree() {
for(auto it : sol) Bridge(min(it.first, it.second), max(it.first, it.second));
}
void Solve(int N) {
n = N;
srand(time(NULL));
vector<int> nodes;
for (int i = 0; i < n; ++i)
nodes.push_back(i);
sol.clear();
solve(nodes);
print_tree();
}
