foo.cc: In function 'bool Findx(int, std::vector<int>)':
foo.cc:7:18: 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<a.size();i++)
      |                 ~^~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:37:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   37 |     for(i=0;i<nc.size();i++)
      |             ~^~~~~~~~~~

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