foo.cc: In function 'int main()':
foo.cc:12:27: 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 < a.size(); i++)cout << a[i];
      |                         ~~^~~~~~~~~~
foo.cc:17:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |         for (int i = 0; i < b.size(); i++)cout << b[i];
      |                         ~~^~~~~~~~~~
foo.cc:19:27: 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 < a.size(); i++)cout << a[i];
      |                         ~~^~~~~~~~~~
foo.cc:21:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |         for (int i = 0; i < b.size(); i++)cout << b[i];
      |                         ~~^~~~~~~~~~
foo.cc:24:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |         for (int i = 0; i < b.size(); i++)cout << b[i];
      |                         ~~^~~~~~~~~~
foo.cc:29:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |         for (int i = 0; i < a.size(); i++)cout << a[i];
      |                         ~~^~~~~~~~~~

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