Compilare: user.cpp: In function ‘void df(int)’: user.cpp:13:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<a[nod].size();i++)df(a[nod][i]); ^ user.cpp: In function ‘int main()’: user.cpp:78:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<a[1].size();i++)sol+=best[a[1][i]]; ^