[Code] F [Explanation] No basis exists [Source rating] 
Cannot be judged
R e l i a b l e
U s u a l l y r e l i a b l e
F a i r l y r e l i a b l e
N o t u s u a l l y r e l i a b l e
U n r e l i a b l e
C a n n o t b e j u d g e d