n, x = map(int, input().split())
a = list(map(int, input().split()))

d = {}
for i in a:
    if not i in d:
        d[i] = 1
    else:
        d[i] += 1

c = 0
for i in d:
    if x - i in d:
        c += d[i] * d[x-i]
print(c)