Compilare: user.cpp: In function ‘int main()’: user.cpp:40:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<vx.size();++i) fout<<vx[i]<<" "; ^ user.cpp:42:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<vy.size();++i) fout<<vy[i]<<" "; ^