/in/foo.cc: In function 'int main()':
/in/foo.cc:10:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 |         for (int i=0;i<=a.size()-1;i++) zc[i+1]=a[i];
      |                      ~^~~~~~~~~~~~
/in/foo.cc:12:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |         while(Change!=a.size()-1)
      |               ~~~~~~^~~~~~~~~~~~
/in/foo.cc:14:25: 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 (rlim==a.size())
      |                     ~~~~^~~~~~~~~~