import bisect



n, x = [ int(v) for v in input().split() ]

num = sorted([ int(v) for v in input().split() ])

s = 0
for i in range(n):
	a = (bisect.bisect_left(num,x-num[i]))
	b = (bisect.bisect_right(num,x-num[i]))
	s += b - a
print(s)