answer.code: In function ‘int main()’:
answer.code:9:49: error: ‘>>’ should be ‘> >’ within a nested template argument list
    9 |     priority_queue<int, vector<int>, greater<int>> pq1 = {};
      |                                                 ^~
      |                                                 > >
answer.code:9:52: error: in C++98 ‘pq1’ must be initialized by constructor, not by ‘{...}’
    9 |     priority_queue<int, vector<int>, greater<int>> pq1 = {};
      |                                                    ^~~
answer.code:10:25: error: in C++98 ‘pq2’ must be initialized by constructor, not by ‘{...}’
   10 |     priority_queue<int> pq2 = {};
      |                         ^~~