Write a program which given a sequence without sentinel of naturals returns "SI
" if in the sequence there
are at least five numbers of four digits with the first digit equal to the last digit, and "NO
" otherwise.
Input A sequence of naturals without sentinel.
Output
A line with "SI
" or "NO
".
Observation
Input
1000 2000 3000 4000 5000 112 1001 2002
Output
NO
Input
10000 20000 1231 2342 100 2542 3453 4554 100 200 399 499 5555
Output
SI