def binarysrch(lst, n, left, right):
	md = (left+right)/2
	if lst[md] == n: return md
	if md == left: return -1
	if lst[md] < n: return binarysrch(lst, n, md+1, right)
	return binarysrch(lst, n, left, md-1)

N, X = map(int, raw_input().split())
a = map(int, raw_input().split())
a.sort()
number = []
count = []
tmp = -1
for i in range(0, N):
	if a[i] == tmp: count[-1] += 1
	else:
		number.append(a[i])
		count.append(1)
		tmp = a[i]
sum = 0
for i in range(0, len(number)):
	srch = binarysrch(number, X-a[i], 0, len(number)-1)
	if srch != -1:
		sum += count[i]*count[srch]
print sum