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 C++ (GCC 9.2.1) (judge verdict: Wrong Answer)

#include<bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
//#include <atcoder/all>
//using namespace atcoder;
using namespace std;
using ll = long long;
using p = pair<int,int>;
const long long INF = 1ll << 60;


int main() {
  int N, K; cin >> N >> K;
  vector<int> A(N);
  rep(i,N)  cin >> A[i];
  ll ans = 0;
  rep(bit,(1<<N)){
    ll sum = 1;
    for(int i = 0; i < N - 1; i++){
      if (bit & (1<<i)) {
        int sa = abs(A[i+1] - A[i]);
        if(sa <= K) sum++;
      }
    }
    ans = max(ans,sum);

  }
 
  cout << ans << endl;


  return 0;
}