Compilare: user.cpp: In function ‘void compress(int, int)’: user.cpp:57:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v[b].size(); ++i) ^ user.cpp: In function ‘void df(int)’: user.cpp:70:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v[nod].size(); ++i) ^ user.cpp:87:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v[nod].size(); ++i) ^ user.cpp:100:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v[nod].size(); ++i) ^