open System
open System.Text

type IO() =
  let size = 1 <<< 12
  let stream = Console.OpenStandardInput()
  let buffer = Array.zeroCreate size
  let ``!`` = byte '!'
  let ``~`` = byte '~'
  let mutable bufferPtr = 0
  
  let hasNextByte =
    let mutable bufferLen = 0
    fun () ->
      if bufferPtr < bufferLen then true
      else
        bufferPtr <- 0
        bufferLen <- stream.Read(buffer, 0, size)
        bufferLen > 0
  let readByte() =
    if hasNextByte() then
      let r = buffer.[bufferPtr]
      bufferPtr <- bufferPtr + 1
      r
    else failwith "error"
  let isAscii c = ``!`` <= c && c <= ``~``
  let nextCharByte() =
    let rec f() =
      let b = readByte()
      if isAscii b then b
      else f()
    f()
  let next() =
    let rec f (sb: StringBuilder) =
      let c = 
        match sb.Length with
        | 0 -> nextCharByte()
        | _ -> readByte()
      if isAscii c then  c |> char |> sb.Append |> f
      else sb 
    f <| new StringBuilder()
    |> fun x -> x.ToString()

  member __.string() = next()
  member __.char()   = nextCharByte() |> char
  member __.int()    = next() |> int
  member __.int64()  = next() |> int64
  member __.float()  = next() |> float

let solve a x =
  let count = a |> Array.countBy id
  let countKey = count |> Array.map fst
  let countMap = count |> Map.ofArray
  let pairNum key1 =
    let val1 = countMap.[key1]
    let key2 = x - key1
    Map.tryFind key2 countMap
    |> function
    | Some val2 -> val1 * val2
    | None -> 0
  countKey
  |> Array.map pairNum
  |> Array.sum
  
let io = new IO()

let N, X = 
  let a = io.int()
  let b = io.int()
  a, b
let a = 
  let t = Array.zeroCreate N
  for i in 0 .. (N - 1) do
    t.[i] <- io.int()
  t

solve a X
|> Console.WriteLine