func_code_string: #include <bits/stdc++.h>   using namespace std;   bool compare(string &s1, string &s2) { return s1.size() < s2.size(); }   bool sortmahstyle(const pair<int, int> &a, const pair<int, int> &b) {     if (a.first < b.first) return true;     return false;   }   long long int const maxm = 1e6;   long long int const minm = -1e9;   void solve() {     int n;     cin >> n;     int next[n + 1][2];     for (int i = 1; i <= n; i++) cin >> next[i][0] >> next[i][1];     vector<int> ans;     ans.push_back(3);     while (ans.size() < n) {       int cur = ans.back();       if (next[next[cur][0]][0] == next[cur][1] ||           next[next[cur][0]][1] == next[cur][1]) {         ans.push_back(next[cur][0]);         ans.push_back(next[cur][1]);       } else {         ans.push_back(next[cur][1]);         ans.push_back(next[cur][0]);       }     }     for (int i = 0; i < n; i++) cout << ans[i] <<    ;   }   int main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     long long int t = 1;     while (t-- > 0) solve();     return 0;   }   