foo.cc: In function 'int main()':
foo.cc:21:37: warning: comparison of integer expressions of different signedness: 'std::priority_queue<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   21 |                         if(bx.size()>xb)
      |                            ~~~~~~~~~^~~
foo.cc:27:32: warning: comparison of integer expressions of different signedness: 'std::priority_queue<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   27 |                 while(bx.size()<xb)
      |                       ~~~~~~~~~^~~

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