foo.cc: In function 'int ee::new_find(std::vector<int>&, int)':
foo.cc:9:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i=0;i<a.size();i++)
                     ~^~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:28:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<a.size();i++)
                 ~^~~~~~~~~

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