from collections import defaultdict

n, x = map(int, input().split())
a = list(map(int, input().split()))

cnt = defaultdict(int)
for k in a:
  cnt[k] += 1
  cnt[x - k] += 0

ans = 0
for k, v in cnt.items():
  if k > x:
    continue
  ans += v * cnt[x - k]

print(ans)