foo.cc: In function 'int main()':
foo.cc:44:10: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::priority_queue<int>::size_type' {aka 'long unsigned int'} [-Wformat=]
   44 | printf("%d",q.size/*返回优先队列中的元素个数*/());
      |         ~^  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |          |                                                |
      |          int                                              std::priority_queue<int>::size_type {aka long unsigned int}
      |         %ld
foo.cc:20:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   20 | scanf("%d",&n);
      | ~~~~~^~~~~~~~~
foo.cc:22:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   22 | scanf("%d %d",&a[i].h,&a[i].t);
      | ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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