foo.cc: In function 'void solve()':
foo.cc:40:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   40 |             for (int i = 0; i < point.size(); i ++)
      |                             ~~^~~~~~~~~~~~~~
foo.cc:41:39: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |                 for (int j = i + 1; j < point.size(); j ++)
      |                                     ~~^~~~~~~~~~~~~~

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