Compilare: user.cpp: In function ‘void DFS(int)’: user.cpp:21:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<a[k].size(); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:41:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (o=0; o<v[nr].size(); ++o) ^ user.cpp:26:14: warning: unused variable ‘x’ [-Wunused-variable] int n,nr,x,y,lv,cv; ^ user.cpp:26:16: warning: unused variable ‘y’ [-Wunused-variable] int n,nr,x,y,lv,cv; ^