Chu trình euler

#include <iostream>
#include <algorithm>
#include <numeric>
#include <set>
#include <queue>
#include <stack>
#include <vector>
#include <climits>
#include <string>
#include <cstdio>
#include <cmath>
#define task "TESTCODE"
using namespace std;
struct T
{
    int node, id;
};
vector<vector<T>> Adj;
bool b[400001];
int n, m, x, y;
vector<int> V;
void read()
{
    cin >> n >> m;
    Adj.resize(n + 1);
    for (int i = 1; i <= m; ++ i)
    {
        cin >> x >> y;
        Adj[x].push_back({y, i});
        Adj[y].push_back({x, i});
        b[i] = true;
    }
}
void solve()
{
    V.push_back(1);
    while (!V.empty())
    {
        int u = V.back();
        bool deleted = false;
        while (!Adj[u].empty() && b[Adj[u].back().id] == false)
        {
            Adj[u].pop_back();
        }
        if (!Adj[u].empty())
        {
            V.push_back(Adj[u].back().node);
            b[Adj[u].back().id] = false;
            Adj[u].pop_back();
        }
        if (u == V.back())
        {
            cout << V.back() << ' ';
            V.pop_back();
        }
    }
}
/// TLE, I don't know why, how the da fuq did that happen
int main()
{
   ios_base::sync_with_stdio(false);
   cin.tie(nullptr);
   //freopen(task".INP", "r", stdin);
   //freopen(task".OUT", "w", stdout);
   read();
   solve();
}