foo.cc: In function 'int main()':
foo.cc:7:14: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
    7 |  if(b.find(a)!=-1)cout<<a<<" is substring of "<<b;
      |     ~~~~~~~~~^~~~
foo.cc:8:19: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
    8 |  else if(a.find(b)!=-1)cout<<b<<" is substring of "<<a;
      |          ~~~~~~~~~^~~~

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