#include "worldmap.h"
#include <bits/stdc++.h>
#define ll long long
#define dbg(x) cerr << #x << ' ' << x << endl;
using namespace std;
vector<int> v;
vector<vector<ll>> adj;
vector<bool> visited;
vector<ll> g1;
vector<ll> g2;
void dfs(ll node, ll par, ll cur)
{
v.push_back(node+1);
visited[node]=1;
if(cur==0)g1.push_back(node);
else g2.push_back(node);
for (auto &&e : adj[node])
{
if(!visited[e])
{
dfs(e,node,cur^1);
v.push_back(node+1);
}
}
}
std::vector<std::vector<int>> create_map(int N, int M, std::vector<int> A, std::vector<int> B)
{
v.clear();
visited.assign(N,0);
adj.assign(N,vector<ll>());
g1.clear();
g2.clear();
for (int i=0;i<M;i++)
{
A[i]--;
B[i]--;
adj[A[i]].push_back(B[i]);
adj[B[i]].push_back(A[i]);
}
dfs(0,0,0);
if(g1.size() > g2.size()) swap(g1,g2);
vector<vector<int>> ans(v.size()+2*g1.size()*2,vector<int>(v.size()+2*g1.size()));
ll sz=v.size()+2*g1.size();
vector<bool> vis(N);
for (int i=0,j=0;i<ans.size()&&j<v.size();i++,j++)
{
vector<int> toadd(sz,v[j]);
ans[i]=toadd;
if(!vis[v[j]-1] && find(g1.begin(),g1.end(),v[j]-1)!=g1.end())
{
vis[v[j]-1]=1;
i++;
vector<int> one;
for (int k=0;k<adj[v[j]-1].size();k++)
{
one.push_back(adj[v[j]-1][k]+1);
one.push_back(v[j]);
}
while(one.size()<sz)one.push_back(v[j]);
ans[i]=one;
i++;
vector<int> two(sz,v[j]);
ans[i]=two;
}
}
return ans;
}
