Compilare: user.cpp: In function ‘int main()’: user.cpp:19:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<V[1].size();++i) ^ user.cpp:22:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(pus[2]<V[2].size()) ^ user.cpp:44:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<Sol.size();++i) g<<Sol[i].first<<' '<<Sol[i].second<<'\n'; ^