import sequtils,strutils,algorithm,math,sugar,macros,strformat
import tables
proc getchar_unlocked():char {. importc:"getchar_unlocked",header: "<stdio.h>" .}
proc scan(): int =
  var minus = false
  while true:
    var k = getchar_unlocked()
    if k == '-' : minus = true
    elif k < '0' or k > '9': break
    else: result = 10 * result + k.ord - '0'.ord
  if minus: result *= -1

proc countSeqFast[T](unSortedKeys:openArray[T]): seq[tuple[key:T,val:int]] =
  if unSortedKeys.len == 0 : return @[]
  var keys = unSortedKeys.sorted(cmp)
  var preKey = keys[0]
  var preVal = 1
  result = @[]
  for i in 1..<keys.len:
    if keys[i] == preKey: preVal += 1
    else:
      result &= (preKey,preVal)
      preKey = keys[i]
      preVal = 1
  result &= (preKey,preVal)

let n = scan()
let x = scan()
var A = newSeq[int](n)
for i in 0..<n:A[i] = scan()
let KV = A.countSeqFast()
let K = KV.mapIt(it.key)
var ans = 0
for ik,k in K:
  let i = K.lowerBound(x-k)
  if K[i] + k == x : ans += KV[i][1]*KV[ik][1]
echo ans