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

if X > 2*10**5:
    exit(print(0))

cnt = [0]*(2*10**5+1)
for a in A:
    cnt[a] += 1
ans = 0
for i in range(X + 1):
    ans += cnt[i]*cnt[X - i]
print(ans)