#include "worldmap.h"
#include <cassert>
#include <queue>
#include <iostream>
std::vector<std::pair<int, int>> spanning_tree(std::vector<std::vector<int>>& adj) {
std::vector<bool> vis(adj.size(), false);
std::vector<std::pair<int, int>> edges;
std::queue<int> q;
q.push(1);
vis[1] = true;
while (!q.empty()) {
int node = q.front();
q.pop();
for (int dest : adj[node]) {
if (!vis[dest]) {
vis[dest] = true;
edges.push_back({node, dest});
q.push(dest);
}
}
}
return edges;
}
void dfs(int node, std::vector<std::vector<int>>& adj, std::vector<bool>& vis, std::vector<int>& order) {
vis[node] = true;
order.push_back(node);
for (int dest : adj[node]) {
if (!vis[dest]) {
dfs(dest, adj, vis, order);
order.push_back(node);
}
}
}
std::vector<std::vector<int>> create_map(int N, int M, std::vector<int> A, std::vector<int> B) {
std::vector<std::vector<int>> adj(N+1, std::vector<int>());
for (int i = 0; i < M; i++) {
adj[A[i]].push_back(B[i]);
adj[B[i]].push_back(A[i]);
}
// this is the M = N(N-1)/2 subtask
int K = 2*N;
std::vector<std::vector<int>> ans(K, std::vector<int>(K, 0));
for (int i = 0; i < K; i++) {
for (int j = 0; j < K; j++) {
if (i % 2 == 0) ans[i][j] = i/2+1;
else ans[i][j] = j%N+1;
}
}
return ans;
}
