answer.code: In function ‘void dfs_and_insert(int, std::set<int>)’:
answer.code:37:16: error: ‘class std::unordered_set<std::pair<int, std::set<int> >, set_hash>’ has no member named ‘contains’
   37 |         if (s3.contains(make_pair(x, s))) return; else s3.insert(make_pair(x, s));
      |                ^~~~~~~~
answer.code:38:17: error: ‘class std::unordered_set<std::set<int>, set_hash>’ has no member named ‘contains’
   38 |         if (!s2.contains(s)) s2.insert(s);
      |                 ^~~~~~~~
answer.code:39:40: error: ‘class std::set<int>’ has no member named ‘contains’
   39 |         for (auto y : to[0][x]) if (!s.contains(y)) {
      |                                        ^~~~~~~~
answer.code: In function ‘void dfs_and_check(int, std::set<int>)’:
answer.code:48:16: error: ‘class std::unordered_set<std::pair<int, std::set<int> >, set_hash>’ has no member named ‘contains’
   48 |         if (s3.contains(make_pair(x, s))) return; else s3.insert(make_pair(x, s));
      |                ^~~~~~~~
answer.code:49:16: error: ‘class std::unordered_set<std::set<int>, set_hash>’ has no member named ‘contains’
   49 |         if (s2.contains(s)) {
      |                ^~~~~~~~
answer.code:53:40: error: ‘class std::set<int>’ has no member named ‘contains’
   53 |         for (auto y : to[1][x]) if (!s.contains(y)) {
      |                                        ^~~~~~~~
answer.code: In function ‘int main()’:
answer.code:61:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   61 |         scanf("%d%d", &n, &m);
      |         ~~~~~^~~~~~~~~~~~~~~~
answer.code:63:22: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   63 |                 scanf("%d%d%d", &a, &b, &c);
      |                 ~~~~~^~~~~~~~~~~~~~~~~~~~~~