from collections import defaultdict

N, X = map(int, input().split())
A = tuple(map(int, input().split()))

D = defaultdict(int)

for i in range(N):
    D[A[i]] += 1

res = 0

for k, v in D.items():
    if X - k in D:
        res += D[X - k] * v

print(res)