N, X = [int(k) for k in input().split()]
a = [int(k) for k in input().split()]

d = {}
for x in a:
    if not x in a:
        d[x] = 1
    else:
        d[x] += 1
c = 0
for x in d:
    if X - x in d:
        c += d[X - x] * d[x]
print(c)