foo.cc: In function 'int main()':
foo.cc:9:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    9 |     for(int i=0;i<s.size();)
      |                 ~^~~~~~~~~
foo.cc:12:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |         for(int j=i;j<i+x.size();j++)
      |                     ~^~~~~~~~~~~
foo.cc:22:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 |             for(int k=0;k<y.size();k++)
      |                         ~^~~~~~~~~

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