foo.cc: In function 'int main()':
foo.cc:13:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   13 |         for (int i = 0; i < a.size(); i++)cout << a[i];
      |                         ~~^~~~~~~~~~
foo.cc:18:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   18 |         for (int i = 0; i < b.size(); i++)cout << b[i];
      |                         ~~^~~~~~~~~~
foo.cc:20:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |         for (int i = 0; i < a.size(); i++)cout << a[i];
      |                         ~~^~~~~~~~~~
foo.cc:22:27: 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 i = 0; i < b.size(); i++)cout << b[i];
      |                         ~~^~~~~~~~~~
foo.cc:25:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |         for (int i = 0; i < b.size(); i++)cout << b[i];
      |                         ~~^~~~~~~~~~
foo.cc:30:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |         for (int i = 0; i < a.size(); i++)cout << a[i];
      |                         ~~^~~~~~~~~~

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