N,X = map(int,input().split())
A = list(map(int,input().split()))
cnt = {}
ans = 0
for a in A:
    if a in cnt:
        cnt[a] += 1
    else:
        cnt[a] = 1

for a in A:
    if X - a in cnt:
        ans += cnt[X-a]
print(ans)