answer.code: In function ‘int main()’:
answer.code:31:1: error: ‘priority_queue’ was not declared in this scope
   31 | priority_queue<pair<int, int>> pq;
      | ^~~~~~~~~~~~~~
answer.code:5:1: note: ‘std::priority_queue’ is defined in header ‘<queue>’; did you forget to ‘#include <queue>’?
    4 | #include <cmath>
  +++ |+#include <queue>
    5 | 
answer.code:31:29: error: expected primary-expression before ‘>’ token
   31 | priority_queue<pair<int, int>> pq;
      |                             ^~
answer.code:31:32: error: ‘pq’ was not declared in this scope
   31 | priority_queue<pair<int, int>> pq;
      |                                ^~