Compilare: main.cpp: In function 'int main()': main.cpp:41:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 41 | for(i = 0; i < s.size(); i++) | ~~^~~~~~~~~~ main.cpp:38:14: warning: unused variable 'n' [-Wunused-variable] 38 | int cer, n, i, j; | ^ main.cpp:38:20: warning: unused variable 'j' [-Wunused-variable] 38 | int cer, n, i, j; | ^