from collections import defaultdict
n, m = map(int, input().split())
if m % 2 == 1:
	print(0)
	exit()
m //= 2
a = list(map(int, input().split()))
s = set()
for i in a:
	s.add(i)
ans = 0
for i in a:
	if m + i in s:
		ans += n - 2
print(ans)