Sequence
Anton is under pressure — he has to submit all the assignments. As often happens — he cannot extend the deadline...
You are given a sequence of integers, and two integers and . You need to find the longest subsequence of the sequence such that (). Here, denotes the number of elements in the sequence . In other words, you need to select a subsequence such that the sum of any two adjacent numbers is not less than and not greater than .
A subsequence of an array is a sequence that can be obtained by deleting several (possibly none) elements from the original sequence.
Input
The first line contains three integers , , (, ).
The second line contains integers () — the description of the sequence.
Output
Output a single integer — the maximum length of such a subsequence .
Examples
Note
In the first example, you can select the subsequence . . .
You can also select .
Scoring
( point): all are the same;
( points): for all ;
( points): ;
( points): ;
( points): ;
( points): ;
( points): ;
( points): ;
( points): ;
( points): no additional constraints.