Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:17:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[cur].size(); i ++) { ^ user.cpp: In function ‘void dfs2(int, int)’: user.cpp:29:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v2[cur].size(); i ++) { ^ user.cpp: In function ‘int main()’: user.cpp:44:13: warning: unused variable ‘k’ [-Wunused-variable] int k, x; f >> d[i]; ^