from bisect import *
N,X = map(int,input().split())
A = list(map(int,input().split()))
A.sort()
ans = 0
for i in range(N):
  b = bisect_left(A,X-A[i])
  if b >= N:
    continue
  if A[i]+A[b] == X:
    br = bisect_right(A,X-A[i])
    ans += (br-b)
print(ans)