foo.cc: In function 'int magic_num(std::string)':
foo.cc:13:23: 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 < s.size(); i++){
      |                     ~~^~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:32:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   32 |         for (int i = 0; i < s.size(); i++){
      |                         ~~^~~~~~~~~~
foo.cc:33:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |             for (int j = 0; j < s.size(); j++){
      |                             ~~^~~~~~~~~~
foo.cc:37:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   37 |         for (int i = 1; i < s.size(); i++){
      |                         ~~^~~~~~~~~~
foo.cc:45:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |         for (int i = 0; i < s.size(); i++){
      |                         ~~^~~~~~~~~~
foo.cc:46:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   46 |             for (int j = i + 1; j < s.size(); j++){
      |                                 ~~^~~~~~~~~~
foo.cc:47:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |                 for (int l = 0; l < s.size(); l++){
      |                                 ~~^~~~~~~~~~
foo.cc:48:43: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |                     for (int r = l + 1; r < s.size(); r++){
      |                                         ~~^~~~~~~~~~

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Found 20 testcases.
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