Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:11:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v[nod].size(); i++){ ~^~~~~~~~~~~~~~ user.cpp:15:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0; j<v[nc].size(); j++){ ~^~~~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:28:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j, n, m, a, b; ^