그랬었습니다

12345678910111213141516171819202122232425262728293031#include #include #include #include using namespace std; int main() { set n_set; list dup; int N, M; cin >> N >> M; for (int i = 0; i > str; n_set.insert(str); } for (int i = 0; i > str; if (n_set.find(str) != n_set.end()) dup.push_back(str); } dup.sort(); cout