Compilare: user.cpp: In function ‘int main()’: user.cpp:25:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( int i = 0; i < s.size(); ++i ) ^ user.cpp:45:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( int j = 0; j < V.size(); ++j ) ^ user.cpp:40:14: warning: unused variable ‘aux’ [-Wunused-variable] char aux; ^ user.cpp:22:9: warning: unused variable ‘f’ [-Wunused-variable] int f(1); ^