Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:19:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<v[x].size(); i++) ^ user.cpp: In function ‘void revdfs(int)’: user.cpp:29:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<vt[x].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:59:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0; j<ans[i].size(); j++) ^