Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:20:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < L[node].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:95:6: warning: unused variable ‘t1’ [-Wunused-variable] int t1=1, t2, t3, t4,mn,mx,MIN=1<<30; ^ user.cpp:95:20: warning: unused variable ‘t4’ [-Wunused-variable] int t1=1, t2, t3, t4,mn,mx,MIN=1<<30; ^