Compilare: main.cpp: In function 'int main()': main.cpp:22:23: 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 < r.length(); i++) | ~~^~~~~~~~~~~~ main.cpp:28:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 28 | while (j < s.length() && s[j] != r[i]) | ~~^~~~~~~~~~~~ main.cpp:31:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 31 | if (j == s.length()) | ~~^~~~~~~~~~~~~