source_code: import java.util.Arrays;
  import java.util.Scanner;
  
  public class SonyaAndHotels {
      public static void main(String[] args) {
          Scanner sc = new Scanner(System.in);
          int n = sc.nextInt();
          int d = sc.nextInt();
          int[] locs = new int[n];
          for (int i = 0; i < n; i++) {
              locs[i] = sc.nextInt();
          }
          Arrays.sort(locs);
          int count = 2;
          for (int i = 0; i < locs.length-1; i++) {
              if(locs[i+1]-locs[i]==2*d){
                  count++;
              }else if(locs[i+1]-locs[i]>2*d){
                  count+=2;
              }
          }
          System.out.println(count);
      }
  }
  