N,X = map(int,input().split())
num = list(map(int,input().split()))
n_list = [0]*100000

for i in num:
    n_list[i] += 1
cnt = 0
right = X
for left in range(X//2):
    cnt+=n_list[left]*n_list[right]*2
    right-=1
if X%2==0:
    cnt += n_list[right]**n_list[right]
print(cnt)