foo.cc: In function 'int main()':
foo.cc:10:18: 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<b.length();i++){
      |                 ~^~~~~~~~~~~
foo.cc:14:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |     for(int i=0;i<a.length();i++){
      |                 ~^~~~~~~~~~~
foo.cc:21:18: 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.length();i++){
      |                 ~^~~~~~~~~~~
foo.cc:23:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |             for(j=0;j<a.length();j++){
      |                     ~^~~~~~~~~~~
foo.cc:27:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |             if(j==a.length() && b[i+j]==' ' && b[i-1]==' '){
      |                ~^~~~~~~~~~~~

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