/in/foo.cc: In function 'int main()':
/in/foo.cc:41:22: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::priority_queue<int>::size_type {aka long unsigned int}' [-Wformat=]
  printf("%d",q.size())
                      ^
/in/foo.cc:42:5: error: expected ';' before 'return'
     return 0;
     ^~~~~~