Compilare: main.cpp: In member function 'number number::operator*(const number&)': main.cpp:23:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(ll i=0;i<v.size();++i) ~^~~~~~~~~ main.cpp:24:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(ll j=0;j<other.v.size();++j){ ~^~~~~~~~~~~~~~~ main.cpp:30:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(ll i=0;i<prod.v.size();++i){ ~^~~~~~~~~~~~~~