answer.code: In function ‘void dfs1(int, int)’:
answer.code:34:15: warning: structured bindings only available with ‘-std=c++17’ or ‘-std=gnu++17’ [-Wc++17-extensions]
   34 |     for (auto [v, w] : g[x])
      |               ^
answer.code: In function ‘void dfs2(int, int)’:
answer.code:56:14: warning: structured bindings only available with ‘-std=c++17’ or ‘-std=gnu++17’ [-Wc++17-extensions]
   56 |         auto [v, w] = g[x][i];
      |              ^
answer.code:66:14: warning: structured bindings only available with ‘-std=c++17’ or ‘-std=gnu++17’ [-Wc++17-extensions]
   66 |         auto [v, w] = g[x][i];
      |              ^
answer.code:70:15: warning: structured bindings only available with ‘-std=c++17’ or ‘-std=gnu++17’ [-Wc++17-extensions]
   70 |     for (auto [v, w] : g[x])
      |               ^
answer.code: At global scope:
answer.code:90:1: error: ‘DFS1’ does not name a type
   90 | DFS1 1
      | ^~~~
answer.code: In function ‘int main()’:
answer.code:76:12: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   76 |     freopen("m.in", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~
answer.code:78:40: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   78 |     for (int i = 1; i <= m; ++ i) scanf("%d", &st[i]), cov[st[i]] = true;
      |                                   ~~~~~^~~~~~~~~~~~~~
answer.code:81:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   81 |         scanf("%d %d %d", &u, &v, &w);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~