# frozen_string_literal: true

N, X = gets.chomp.split.map(&:to_i)
A = gets.chomp.split.map(&:to_i)

c = {}
A.each do |a|
  c[a] ||= 0
  c[a] += 1
end
C = c

B = A.uniq.sort
R = (0..(B.size - 1)).map do |i|
  s = X - B[i]
  j = B[i..(N - 1)].bsearch_index { |x| x >= s }
  if j.nil? || B[i + j] != s
    0
  elsif j.zero?
    C[s]
  else
    C[s] * 2
  end
end
RESULT = R.sum

puts RESULT