source_code: import java.util.Scanner;
  
  public class R495A {
  	public static void main(String[] args) {
  		Scanner scan=new Scanner(System.in);
  		int n=scan.nextInt(), k=scan.nextInt();
  		int[] a=new int[n];
  		for(int i=0;i<n;i++) a[i]=scan.nextInt();
  		int res=2;
  		for(int i=0;i<n-1;i++) {
  			if(a[i+1]-a[i]>2*k) res+=2;
  			else if(a[i+1]-a[i]==2*k) res++;
  		}
  		System.out.println(res);
  	}
  }