#include <bits/stdc++.h>
using namespace std;
typedef vector<int> vi;
vector<vi> world_map;
vi adj[50], tree[50];
int vis[50], par[50];
int sz[50], depth[50];
pair<int, int> pos[50];
void DFS(int node, int prev, int d)
{
vis[node] = 1;
depth[node] = d;
sz[node] = 1;
for (int v : adj[node])
{
if (v == prev || vis[v]) continue;
par[v] = node;
tree[node].push_back(v);
tree[v].push_back(node);
DFS(v, node, d + 1);
sz[node] += sz[v];
}
}
void Build(int node, int prev, int left, int right, int level)
{
for (int i = left; i <= right; ++i) {
world_map[level * 2][i] = node;
}
for (int i = left; i <= right; ++i)
if ((i - left) % 2 == 1)
{
world_map[level * 2 + 1][i] = node;
if (level > 0)
world_map[level * 2 - 1][i] = node;
}
pos[node] = {level * 2, left + 1};
for (int child : tree[node])
{
if (child == prev) continue;
++left;
Build(child, node, left, left + sz[child] * 2 - 2, level + 1);
left += sz[child] * 2 - 1;
}
}
vector<vi> create_map(int n, int m, vi a, vi b)
{
world_map.assign(n * 2 - 1, vi(n * 2 - 1, 0));
for (int i = 1; i <= n; ++i)
{
adj[i].clear();
tree[i].clear();
vis[i] = 0;
}
for (int i = 0; i < m; ++i) {
adj[a[i]].push_back(b[i]);
adj[b[i]].push_back(a[i]);
}
DFS(1, 0, 0);
Build(1, 0, 0, 2 * n - 2, 0);
for (int i = 1; i <= n; ++i)
for (int v : adj[i]) {
if (depth[v] > depth[i] && par[v] != i)
{
auto &[x, y] = pos[i];
world_map[x][y] = v;
y += 2;
}
}
for (int i = 0; i < 2 * n - 1; ++i)
for (int j = 0; j < 2 * n - 1; ++j)
if (world_map[i][j] == 0)
{
if (i > 0) world_map[i][j] = world_map[i - 1][j];
else world_map[i][j] = world_map[i][j - 1];
}
return world_map;
}
