#!/usr/bin/ruby

N, X = gets.split.map(&:to_i)
a = gets.split.map(&:to_i)
hash = {}
a.each do |a|
  hash[a] ||= 0
  hash[a] += 1
end

count = 0
i = 0
while i < a.length do
  num1 = a[i]
  num2 = X - num1
  if num1 == num2
    if hash[num2] >= 2
      count += hash[num]-1
    elsif hash[num2] >= 1
      count += hash[num2]
    end
  else
    if hash[num2]
      count += hash[num2]
    end
  end
  i += 1
end

puts count