Compilare: main.cpp: In function 'int main()': main.cpp:18:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 18 | for(int i = 0;i < s.size();i++) | ~~^~~~~~~~~~ main.cpp:31:18: 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(i < s.size()) | ~~^~~~~~~~~~ main.cpp:50:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 50 | if(i < s.size()) | ~~^~~~~~~~~~