import strutils, sequtils, tables, sets

let
  tmp, arr = map(split readLine stdin, parseInt)
  (N, X) = (tmp[0], tmp[1])
var
  a = initCountTable[int]()
  b = initSet[int]()
  ans = 0
  j = 0

for i, ai in arr:
  inc a, ai
  incl b, ai

for k, v in a:
  if j * 2 >= a.len - 1: break

  if X - k in a:
    ans += a[k] * a[X - k] * (2 - int(k == X - k))
  j += 1

echo ans