Compilare: user.cpp: In function ‘void DFS(int, int)’: user.cpp:52:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<G[x].size();i++){ ^ user.cpp: In function ‘void read()’: user.cpp:22:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("darb.in","r",stdin); ^ user.cpp:23:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:28:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^ user.cpp: In function ‘void write()’: user.cpp:45:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("darb.out","w",stdout); ^