text: # https://www.hackerrank.com/challenges/pairs/problem
  
  #!/bin/python3
  
  import math
  import os
  import random
  import re
  import sys
  
  #
  # Complete the 'pairs' function below.
  #
  # The function is expected to return an INTEGER.
  # The function accepts following parameters:
  #  1. INTEGER k
  #  2. INTEGER_ARRAY arr
  #
  
  def pairs(k, arr):
      d,ans = {z : 1 for i,z in enumerate(arr)},0
      for z in d:
          if((z+k) in d): ans+=1
      return ans
  
  if __name__ == '__main__':
      fptr = open(os.environ['OUTPUT_PATH'], 'w')
  
      first_multiple_input = input().rstrip().split()
  
      n = int(first_multiple_input[0])
  
      k = int(first_multiple_input[1])
  
      arr = list(map(int, input().rstrip().split()))
  
      result = pairs(k, arr)
  
      fptr.write(str(result) + '\n')
  
      fptr.close()