foo.cc: In function 'int ANS(std::vector<int>&)':
foo.cc:8:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    8 |  for(int i=0; i<v.size()-1; i++)
      |               ~^~~~~~~~~~~
foo.cc:9:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    9 |   for(int j=i+1; j<v.size(); j++)
      |                  ~^~~~~~~~~

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