Compilare: main.cpp: In function 'int main()': main.cpp:77:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 77 | for(j=0;j<s.size();j++) | ~^~~~~~~~~ main.cpp:67:21: warning: unused variable 'c' [-Wunused-variable] 67 | int cer,i,j,x,y,c; | ^