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

count = {}
for i in l:
    if i in count:
        count[i] += 1
    else:
        count[i] = 1

answer = 0
for i in count:
    if x-i in count:
        answer += count[i] * count[x-i]

print(answer)