Compilare: user.cpp: In function ‘int main()’: user.cpp:13:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<n.size();++i) ^ user.cpp:19:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i!=0&&i!=n.size()-1) s2++; ^ user.cpp:9:10: warning: unused variable ‘spatiu’ [-Wunused-variable] char spatiu[]={' ','-'},st=0; ^ user.cpp:9:29: warning: unused variable ‘st’ [-Wunused-variable] char spatiu[]={' ','-'},st=0; ^