foo.cc: In function 'int main()':
foo.cc:11:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 |         for(int i=1;i<=s.size() ;i++)
      |                     ~^~~~~~~~~~
foo.cc:14:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |                 for(int j=0;j<s.size() -i+1;j++)
      |                             ~^~~~~~~~~~~~~~
foo.cc:17:40: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |                         for(int j1=0;j1<s1.size() ;j1++)
      |                                      ~~^~~~~~~~~~

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