#include "worldmap.h"
#include <bits/stdc++.h>
using namespace std;
/*
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
*/
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
template <class T> using PQMax = priority_queue<T>;
template <class T> using PQMin = priority_queue<T, vector<T>, greater<T>>;
template <class T1, class T2>
void maximize(T1 &a, T2 b){
if (b > a) a = b;
}
template <class T1, class T2>
void minimize(T1 &a, T2 b){
if (b < a) a = b;
}
template <class T>
void read(T &number)
{
bool negative = false;
register int c;
number = 0;
c = getchar();
while (c != '-' && !isalnum(c)) c = getchar();
if (c=='-'){
negative = true;
c = getchar();
}
for (; (c>47 && c<58); c=getchar())
number = number *10 + c - 48;
if (negative)
number *= -1;
}
template <class T, class ...Ts>
void read(T &a, Ts& ... args){
read(a);
read(args...);
}
/*
struct Node
{
int node, len;
Node() {node = len = 0;}
Node(int node, int len) {this -> node = node, this -> len = len;}
};
typedef vector<Node> vg;
*/
#define fi first
#define se second
#define FOR(type, i, a, b) for(type i = (a); i <= (b); i++)
#define REV(type, i, b, a) for(type i = (b); i >= (a); i--)
#define testBit(n, bit) (((n) >> (bit)) & 1)
#define flipBit(n, bit) ((n) ^ (1ll << (bit)))
#define cntBit(n) __builtin_popcount(n)
#define cntBitll(n) __builtin_popcountll(n)
#define log2(n) (31 - __builtin_clz(n))
#define log2ll(n) (63 - __builtin_clzll(n))
#define CURRENT_TIMESTAMP chrono::steady_clock::now().time_since_epoch().count()
#define randomize mt19937_64 mt(CURRENT_TIMESTAMP)
#define MAX 1000001
#define MOD 1000000007
int n, m;
vector<int> graph[MAX];
namespace Subtask12 {
vector<int> euler;
void dfs(int u, int p) {
cerr << u << ' ' << p << '\n';
euler.push_back(u);
bool oke = false;
for (int v: graph[u]) if (v != p)
dfs(v, u), euler.push_back(u);
}
vector<vector<int>> solve() {
dfs(1, 0);
int sz = euler.size();
return vector<vector<int>>(sz, euler);
}
}
void clear();
std::vector<std::vector<int>> create_map(int _N, int _M, std::vector<int> _A, std::vector<int> _B) {
clear();
n = _N, m = _M;
for (int i = 0; i < m; i++) {
int u = _A[i], v = _B[i];
graph[u].push_back(v);
graph[v].push_back(u);
}
return Subtask12::solve();
// return ans;
}
void clear(){
Subtask12::euler.clear();
FOR(int, i, 1, n) graph[i].clear();
n = m =0;
}
