Compilare: user.cpp: In function ‘bool is_ok(int)’: user.cpp:38:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < vecini[nod].size(); ++i) ^ user.cpp: In function ‘void solve()’: user.cpp:67:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < vecini[nod].size(); ++i) ^ user.cpp:72:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < vecini[nod].size(); ++i) ^ user.cpp:79:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i<vecini[nod].size(); ++i){ ^ user.cpp:83:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j<vecini[nod2].size(); ++j) ^