foo.cc: In function 'int main()':
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 i=0;i<s.size();)
      |                     ~^~~~~~~~~
foo.cc:18:31: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   18 |                         for(;j<s.size();j++)
      |                              ~^~~~~~~~~
foo.cc:37:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   37 |                 if(i==s.size())
      |                    ~^~~~~~~~~~

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