source_code: import java.util.*;
  import java.io.*; 
  import java.text.DecimalFormat;
  
  public class Main{
      final long mod = (int)1e9+7, IINF = (long)1e19;
      final int MAX = (int)5e5+1, MX = (int)1e7+1, INF = (int)1e9, root = 3;
      DecimalFormat df = new DecimalFormat("0.0000000000000");
      double eps = 1e-9, PI = 3.141592653589793238462643383279502884197169399375105820974944;
      static boolean multipleTC = false, memory = false;
      FastReader in;PrintWriter out;
      public static void main(String[] args) throws Exception{
          if(memory)new Thread(null, new Runnable() {public void run(){try{new Main().run();}catch(Exception e){e.printStackTrace();}}}, "1", 1 << 28).start();
          else new Main().run();
      }
  
      void run() throws Exception{
          in = new FastReader();
          out = new PrintWriter(System.out);
          for(int i = 1, T= (multipleTC)?ni():1; i<= T; i++)solve(i);
          out.flush();
          out.close();
      }
      
      void solve(int TC) throws Exception{
          int n = ni();
          long d = nl();
          long ans = 2;
          long[] p = new long[n];
          for(int i = 0; i< n; i++)p[i] = nl();
          for(int i = 1; i< n; i++){
              if(p[i]-p[i-1] == 2*d)ans++;
              else if(p[i]-p[i-1]>2*d)ans+=2;
          }
          pn(ans);
      }
          
      int[] reverse(int[] a){
          int[] o = new int[a.length];
          for(int i = 0; i< a.length; i++)o[i] = a[a.length-i-1];
          return o;   
      }
  
      int[] sort(int[] a){
          if(a.length==1)return a;
          int mid = a.length/2;
          int[] b = sort(Arrays.copyOfRange(a,0,mid)), c = sort(Arrays.copyOfRange(a,mid,a.length));
          for(int i = 0, j = 0, k = 0; i< a.length; i++){
              if(j<b.length && k<c.length){
                  if(b[j]<c[k])a[i] = b[j++];
                  else a[i] = c[k++];
              }else if(j<b.length)a[i] = b[j++];
              else a[i] = c[k++];
          }
          return a;
      }
  
      long[] sort(long[] a){
          if(a.length==1)return a;
          int mid = a.length/2;
          long[] b = sort(Arrays.copyOfRange(a,0,mid)), c = sort(Arrays.copyOfRange(a,mid,a.length));
          for(int i = 0, j = 0, k = 0; i< a.length; i++){
              if(j<b.length && k<c.length){
                  if(b[j]<c[k])a[i] = b[j++];
                  else a[i] = c[k++];
              }else if(j<b.length)a[i] = b[j++];
              else a[i] = c[k++];
          }
          return a;
      }
  
      long gcd(long a, long b){return (b==0)?a:gcd(b,a%b);}
      int gcd(int a, int b){return (b==0)?a:gcd(b,a%b);}
      int bitcount(long n){return (n==0)?0:(1+bitcount(n&(n-1)));}
      void p(Object o){out.print(o);}
      void pn(Object o){out.println(o);}
      void pni(Object o){out.println(o);out.flush();}
      String n(){return in.next();}
      String nln(){return in.nextLine();}
      int ni(){return Integer.parseInt(in.next());}
      long nl(){return Long.parseLong(in.next());}
      double nd(){return Double.parseDouble(in.next());}
  
      class FastReader{
          BufferedReader br;
          StringTokenizer st;
          public FastReader(){
              br = new BufferedReader(new InputStreamReader(System.in));
          }
  
          public FastReader(String s) throws Exception{
              br = new BufferedReader(new FileReader(s));
          }
  
          String next(){
              while (st == null || !st.hasMoreElements()){
                  try{
                      st = new StringTokenizer(br.readLine());
                  }catch (IOException  e){
                      e.printStackTrace();
                  }
              }
              return st.nextToken();
          }
  
          String nextLine(){
              String str = "";
              try{
                  str = br.readLine();
              }catch (IOException e){
                  e.printStackTrace();
              }   
              return str;
          }
      }
  }