Compilare: main.cpp: In function 'void dfs(int)': main.cpp:13:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[nod].size(); ++i) ~~^~~~~~~~~~~~~~~ main.cpp: In function 'void dfs2(int)': main.cpp:26:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < tr[nod].size(); ++i) ~~^~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:67:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < ordine.size(); ++i) ~~^~~~~~~~~~~~~~~