n, X = [int(x) for x in input().split(' ')]
nums = [int(x) for x in input().split(' ')]

nums_count = {}
count = 0

for i in nums:
    if i in nums_count:
        nums_count[i] += 1
    
    else:
        nums_count[i] = 1

for i in nums_count.keys():
    x = X - i
    
    if x in nums_count:
        count += nums_count[i] * nums_count[x]

print(count)