#!/usr/bin/ruby

N, X = gets.split.map(&:to_i)
a = gets.split.map(&:to_i)
warn 'array size unmatched!' if a.length!=N
hash = {}
a.each do |n|
  hash[n] ||= 0
  hash[n] += 1
end

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

puts count