Compilare: main.cpp: In function 'int dfs(int)': main.cpp:25:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < lis[nod].size(); i++) ~~^~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:56:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v.size(); i++) ~~^~~~~~~~~~ main.cpp:33:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("divisorgraph.in","r",stdin); ^ main.cpp:34:43: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("divisorgraph.out","w",stdout); ^ main.cpp:36:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&t); ^ main.cpp:39:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&e); ^ main.cpp:46:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&x,&y); ^