Compilare: main.cpp: In function 'void dfs(int)': main.cpp:18:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[nod].size(); ++i) ~~^~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:66:13: warning: unused variable 'a' [-Wunused-variable] int a, b; ^ main.cpp:66:16: warning: unused variable 'b' [-Wunused-variable] int a, b; ^