Compilare: user.cpp: In function ‘void bfs(int)’: user.cpp:23:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v[k].size(); i++) ^ user.cpp: In function ‘void dfs1(int)’: user.cpp:46:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i <v[k].size (); i++) ^ user.cpp: In function ‘void dfs2(int)’: user.cpp:72:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v[k].size(); i++) ^