#include<bits/stdc++.h> using namespace std; vector<int> ans; vector<int> v[50]; void dfs(int u, int k) { for(int i = 0; i < v[k].size(); i++) { if(v[k][i] != u) { ans.push_back(w); dfs(k,v[k][i]); } } if(k != 1) ans.push_back(k); } vector<vector<int>> create_map(int N, int M, vector<int> A, vector<int> B){ if(M == 0) { vector<vector<int>> vec(1, vector<int>(1,1)); return vec; } for(int i = 0; i <= 40; i++) v[i].clear(); for(int i = 0; i < M; i++) { v[A[i]].push_back(B[i]); v[B[i]].push_back(A[i]); } ans.clear(); dfs(0, 1); int n = ans.size(); vector<vector<int>> ans1(n, vector<int>(n)); for(int i = 0; i < ans.size(); i++) { for(int j = 0; j < ans.size(); j++){ ans1[i][j] = ans[j]; } } return ans1; }

worldmap.cpp: In function 'void dfs(int, int)':
worldmap.cpp:8:27: error: 'w' was not declared in this scope
    8 |             ans.push_back(w);
      |                           ^