foo.cc: In function 'int main()':
foo.cc:8:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    8 |     for(int i=0;i<s.size()/2+1;i++)
      |                 ~^~~~~~~~~~~~~
foo.cc:14:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |     if(cnt==s.size()/2+1)
      |        ~~~^~~~~~~~~~~~~~

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