There is a big staircase with $N$ steps (numbered $1$ through $N$) in ChefLand. Let's denote the height of the top of step $i$ by $h_i$. Chef Ada is currently under the staircase at height $0$ and she wants to reach the top of the staircase (the top of the last step). However, she can only jump from height $h_i$ to the top of a step at height $h_f$ if $h_f-h_i \le K$. To help Ada, we are going to construct some intermediate steps; each of them may be constructed between any two steps, or before the first step, and have any height. What is the minimum number of steps that need to be added to the staircase so that Ada could reach the top?

-----Input-----
- The first line of the input contains a single integer $T$ denoting the number of test cases. The description of $T$ test cases follows.
- The first line of each test case contains two space-separated integers $N$ and $K$.
- The second line contains $N$ space-seperated integers $h_1, h_2, \dots, h_N$.

-----Output-----
For each test case, print a single line containing one integer — the minimum required number of steps.

-----Constraints-----
- $1 \le T \le 64$
- $1 \le N \le 128$
- $1 \le K \le 1,024$
- $1 \le h_i \le 1,024$ for each valid $i$
- $h_i < h_{i+1}$ for each valid $i$

-----Example Input-----
1
4 3
2 4 8 16

-----Example Output-----
3

```python

USER_FILENAME = "<user_code>"
import sys, json, builtins
import math, heapq, bisect, itertools, functools, collections, statistics, fractions, decimal, operator, array, random, re, string, os, pathlib
try:
    import resource as _res
except Exception:
    _res = None
from collections import Counter, defaultdict, deque, OrderedDict
from functools import lru_cache, reduce
from itertools import accumulate, permutations, combinations, product
from math import gcd, ceil, floor, sqrt
from decimal import Decimal
try:
    from typing import *
except Exception:
    pass
try:
    sys.setrecursionlimit(1_000_000)
except Exception:
    pass
try:
    import site as _site
    try:
        _sys_sites = _site.getsitepackages() if hasattr(_site, "getsitepackages") else []
        for _p in _sys_sites:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
    try:
        _usp = _site.getusersitepackages()
        if isinstance(_usp, str):
            _usp = [_usp]
        for _p in _usp:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
except Exception:
    pass

ns = {"__name__": "__main__"}
for _k, _v in list(globals().items()):
    if not _k.startswith("_"):
        ns[_k] = _v
_CODE = '# cook your dish here\n\nimport numpy as np\n \n\ndef minstairs(n,k):\n stairsHeight=[]\n stairs=0\n current = 0\n stairsHeight=list(map(int, input().split()))\n stairsHeight=np.array(stairsHeight)\n curr=0\n for i in range(n):\n  if stairsHeight[i]-curr<=k:\n   curr=stairsHeight[i]\n  else:\n   if (stairsHeight[i]-curr)%k==0:\n    stairs+=((stairsHeight[i]-curr)//k)-1\n   else:\n    stairs+=(stairsHeight[i]-curr)//k\n   curr=stairsHeight[i]\n return stairs\n  \nT=int(input())\nfor i in range(T):\n n,k =list(map(int,input().split()))\n print(minstairs(n,k))\n'
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

```

Measured memory_bytes: 6169660