Compilare: main.cpp: In function 'void bfs(int)': main.cpp:28:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[nod].size(); ++i) ~~^~~~~~~~~~~~~~~ main.cpp:38:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < tr[nod].size(); ++i) ~~^~~~~~~~~~~~~~~~