Compilare: user.cpp: In function ‘int main()’: user.cpp:20:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[x%prim].size();++i) ^ user.cpp:27:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[x%prim].size();++i) ^ user.cpp:35:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[x%prim].size();++i) ^