foo.cc: In function 'int main()':
foo.cc:62:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |  for(int i=index1;i<s1.size();i++)
      |                   ~^~~~~~~~~~
foo.cc:108:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  108 |  for(int i=index1;i<s2.size();i++)
      |                   ~^~~~~~~~~~

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