1022 - K-diff subsequence

Time Limit: 5s Memory Limit: 128MB

Submissions: 246 Solved: 79
Description
If the difference between any two adjancent elements in a sequence is not more than K, then we call this sequence is a K-diff sequence. A subsequence of some sequence is a new sequence which is formed from the original sequence by deleting some of the elements without changing the order. For example, "1 3 4 6" is a 2-diff subsequence of "1 2 3 4 5 6 7". Now give you K and a sequence whose length is N, try to find out the maximum length of the K-diff subsequence of the original sequence.
Input
The first line contains a integer T, which means there are T test cases. For each test case: The first line contains two integers: N(0 < N < 102400), K(0 <= K < 100000). The second line contains n positive integers: the orginal sequence.
Output
For each test case: Output only one line with the maximum length of the K-diff subsequence.
Sample Input
2
5 2
1 3 2 2 3
5 2
1 3 4 7 2
Sample Output
5
4
Hint
" n positive integers " 0< X <2^31
Source
lshmouse