Compilare: user.cpp: In function ‘int main()’: user.cpp:39:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < root.size(); ++i){ ^ user.cpp:53:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[u].size(); ++i){ ^ user.cpp:54:52: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < q[v[u][i]].size(); ++j){ ^ user.cpp:55:62: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(q[v[u][i]][j].father < stiva.size() + 1){ ^