Problem:
Score : 400 points

Problem Statement

You are given a sequence A_1, A_2, ..., A_N and an integer K.

Print the maximum possible length of a sequence B that satisfies the following conditions:

B is a (not necessarily continuous) subsequence of A.

For each pair of adjacents elements of B, the absolute difference of the elements is at most K.

Constraints

1 \leq N \leq 300,000

0 \leq A_i \leq 300,000

0 \leq K \leq 300,000

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N K
A_1
A_2
:
A_N

Output

Print the answer.

Sample Input 1

10 3
1
5
4
3
8
6
9
7
2
4

Sample Output 1

7

For example, B = (1, 4, 3, 6, 9, 7, 4) satisfies the conditions.

It is a subsequence of A = (1, 5, 4, 3, 8, 6, 9, 7, 2, 4).

All of the absolute differences between two adjacent elements (|1-4|, |4-3|, |3-6|, |6-9|, |9-7|, |7-4|) are at most K = 3.

Solution in PyPy3 (7.3.0) (judge verdict: Time Limit Exceeded)

n,k = map(int,input().split())
a = []
for _ in range(n):
  a.append(int(input()))  
b = [0]*n
c = [0]*n

for i in range(n):
  temp = [1]
  for j in range(i-1,-1,-1):
    if c[j] == 0:
      x = a[j]-a[i]
      if abs(x)<=3:
        temp.append(b[j]+1)
        c[j] = 1
  b[i] = max(temp)
print(max(b))