Compilare: user.cpp: In function ‘void Union(const int&, const int&, std::vector<int>&)’: user.cpp:54:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(parent[i]==parent[v2] && i!=v2) parent[i]=parent[v1]; ^ user.cpp:62:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(parent[i]==parent[v1] && i!=v1) parent[i]=parent[v2]; ^ user.cpp: In function ‘int main()’: user.cpp:98:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<kruskal.size();i++) fout<<kruskal[i]<<'\n'; ^ user.cpp:74:8: warning: unused variable ‘aux’ [-Wunused-variable] wEdge aux; ^