Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:20:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v[cur].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:44:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<w.size(); i++) { ^ user.cpp:52:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int son=0; son<v[cur].size(); son++) ^