Compilare: main.cpp: In function 'int main()': main.cpp:13:22: 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++){ | ~~^~~~~~~~~~ main.cpp:14:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 14 | if(i < s.size() - 1){ | ~~^~~~~~~~~~~~~~ main.cpp:16:33: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 16 | while(st >= 0 && st < s.size() && s[st] == s[dr]){ | ~~~^~~~~~~~~~ main.cpp:22:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 22 | while(st >= 0 && st < s.size() && s[st] == s[dr]){ | ~~~^~~~~~~~~~