n, x = gets.split.map(&:to_i)
a = gets.split.map(&:to_i)
table = a.group_by(&:itself).map { |k,v| [k,v.size] }.to_h
count = 0
if table[x.fdiv(2)]
    count += table[x.fdiv(2)]**2
end
table.keys.each do |k|
    if x - k < 0
        next
    end
    count = table[k] * (table[x - k] || 0)
end
puts count