Compilare: main.cpp: In function 'void df(int, int)': main.cpp:27:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v[nod].size(); i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'void df2(int, int, int)': main.cpp:52:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v[nod].size(); i++) ~^~~~~~~~~~~~~~ main.cpp:61:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v[nod].size(); i++) ~^~~~~~~~~~~~~~