import java.util.Arrays;
import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        scanner.nextInt();
        while (scanner.hasNext()){
            int n = scanner.nextInt();
            int[] nums = new int[n];
            int k = scanner.nextInt();
            for (int i = 0; i < n; i++) {
                nums[i] = scanner.nextInt();
            }
            System.out.println(getResult(nums,n,k));
        }
        scanner.close();
    }

    private static int getResult(int[] nums, int n, int k) {
        Arrays.sort(nums);
        int minX = nums[0]-k;
        nums[0] = minX;
        for (int i = 1; i < n; i++) {
            if(nums[i-1]+1>=nums[i]-k&&nums[i-1]+1<=nums[i]+k){
                nums[i] = nums[i-1]+1;
            }else if(nums[i-1]+1<nums[i]-k){
                nums[i] = nums[i]-k;
            }else{
                nums[i] = nums[i]+k;
            }
        }
        int cnt = 1;
        Arrays.sort(nums);
        for (int i = 1; i < n; i++) {
            if(nums[i]!=nums[i-1]){
                cnt++;
            }
        }
        return cnt;
    }
}