/in/foo.cc: In function 'int findnot(std::vector<int>&)':
/in/foo.cc:6:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<x.size();i++)
              ~^~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:33:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if(j==x.size())
        ~^~~~~~~~~~
/in/foo.cc:38:8: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if(j==x.size())
       ~^~~~~~~~~~
/in/foo.cc:43:7: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if(j==x.size())
      ~^~~~~~~~~~
/in/foo.cc:50:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<x.size();i++)
              ~^~~~~~~~~