foo.cc: In function 'void Output(std::vector<int>&)':
foo.cc:8:22: 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<t.size();i++)
      |                     ~^~~~~~~~~
foo.cc: In function 'int Count(std::vector<int>&)':
foo.cc:15:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |         for(int i=0;i<s.size();i+=2)
      |                     ~^~~~~~~~~
foo.cc:17:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |                 for(int j=i+1;j<s.size();j+=2)
      |                               ~^~~~~~~~~

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