foo.cc: In function 'int main()':
foo.cc:10:15: 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<s.size();i++)
      |              ~^~~~~~~~~
foo.cc:15:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |    for(int j=i+1;j<s.size();j++)
      |                  ~^~~~~~~~~
foo.cc:19:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   19 |  for(int i=0;i<s.size()-cnt+2;i++)
      |              ~^~~~~~~~~~~~~~~

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