Compilare: main.cpp: In function 'int main()': main.cpp:35:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 35 | for(int st = 0; st <= s1.size(); st ++) | ~~~^~~~~~~~~~~~ main.cpp:37:32: 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 dr = 0; dr <= s1.size(); dr ++) | ~~~^~~~~~~~~~~~