foo.cc: In function 'bool Search(std::vector<int>&, int)':
foo.cc:7:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    7 |         for (int i=0; i<v.size(); i++)
      |                       ~^~~~~~~~~
foo.cc: In function 'void Output(std::vector<int>&)':
foo.cc:15:23: 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<v.size(); i++)
      |                      ~^~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:43:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |         for (int i=0; i<a.size(); i++)
      |                       ~^~~~~~~~~

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