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  1. #include <iostream>
  2. #include <queue>
  3. #include <tuple>
  4. #include <boost/ptr_container/ptr_vector.hpp>
  5.  
  6. struct point
  7. {
  8.     int x;
  9.     int y;
  10. };
  11.  
  12. bool operator<(const point& lhs, const point& rhs)
  13. {
  14.     return std::tie(lhs.x, lhs.y) < std::tie(rhs.x, rhs.y);
  15. }
  16.  
  17. std::ostream& operator<<(std::ostream& out, const point& p)
  18. {
  19.     return out << p.x << ' ' << p.y;
  20. }
  21.  
  22. namespace detail
  23. {
  24.     template<typename>
  25.     struct ptr_less;
  26.  
  27.     template<typename T>
  28.     struct ptr_less<T*>
  29.     {
  30.         bool operator()(const T& lhs, const T& rhs)
  31.         {
  32.             return lhs < rhs;
  33.         }
  34.     };
  35. }
  36.  
  37. template<typename T>
  38. using ptr_priority_queue = std::priority_queue<T*, boost::ptr_vector<T>, detail::ptr_less<T*>>;
  39.  
  40. int main()
  41. {
  42.     // std::priority_queue<point*, boost::ptr_vector<point>, detail::ptr_less<point*>> points;
  43.     ptr_priority_queue<point> points;
  44.  
  45.     points.push(new point{4, 1});
  46.     points.push(new point{3, 2});
  47.     points.push(new point{1, 6});
  48.     points.push(new point{3, 4});
  49.  
  50.     while (!points.empty())
  51.     {
  52.         std::cout << points.top() << std::endl;
  53.         points.pop();
  54.     }
  55.  
  56.     return 0;
  57. }
  58.  
  59. // Sample output:
  60. // 4 1
  61. // 3 4
  62. // 3 2
  63. // 1 6
Compilation error #stdin compilation error #stdout 0s 0KB
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stdin
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Standard input is empty
compilation info 
prog.cpp:4:46: fatal error: boost/ptr_container/ptr_vector.hpp: No such file or directory
compilation terminated.
stdout
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Standard output is empty
https://ideone.com/rqit9
language:
C++14 (gcc 8.3)
created:
13 years ago
visibility:
public

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