Compilare: user.cpp: In function ‘int main()’: user.cpp:44:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<d.size(); i++)out<<d[i]<<" "; ^ user.cpp:17:12: warning: unused variable ‘y’ [-Wunused-variable] int x, y=0, a, b, c, l; ^ user.cpp:45:17: warning: ‘l’ may be used uninitialized in this function [-Wmaybe-uninitialized] out<<"\n"<<l; ^