#include<bits/stdc++.h>
using namespace std;
typedef long long int uli;
int rint(char nxt){
  char ch=getchar();
  int v=0;
  int sgn=1;
  if(ch=='-')sgn=-1;  
  else{
    assert('0'<=ch&&ch<='9');
    v=ch-'0';
  }
  while(true){
    ch=getchar();
    if('0'<=ch && ch<='9')v=v*10+ch-'0';
    else{
      assert(ch==nxt);
      break;
    }
  }
  return v*sgn;
}
int main(){
//  freopen("secret/0.in","r",stdin);
//  freopen("secret/0.out","w",stdout);
  int t=rint('\n');
  assert(1<=t&&t<=64);
  while(t--){
    int n=rint(' ');
    assert(1<=n&&n<=128);
    int k=rint('\n');

    assert(1<=k&&k<=1024);    
    vector<int>h(n);
    for(int i=0;i<n;i++){
      h[i]=rint(i==n-1?'\n':' ');
      assert(1<=h[i]&&h[i]<=1024);
    }
    for(int i=0;i+1<n;i++)assert(h[i]<h[i+1]);
    int y=0;
    int ans=0;
    for(int i=0;i<n;){
      if(y+k>=h[i]){//can jump to the next step?
        y=h[i++];
      }
      else{
        y+=k;//create an intermediate step
        ans++;
      }
    }
    printf("%d\n",ans);
  }
  assert(getchar()==EOF);
  return 0;
}