Compilare: user.cpp: In function ‘bool dfs(int)’: user.cpp:12:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<adj[u].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:26:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("revolutie.in","r",stdin); ^ user.cpp:27:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("revolutie.out","w",stdout); ^ user.cpp:29:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:33:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&a[i][j]); ^