N,X = map(int,input().split())
A = list(map(int,input().split()))
C = {}
for i in range(N):
    if A[i] not in C:
        C[A[i]] = 0
    C[A[i]] += 1
cnt = 0
for i in range(N):
    a = A[i]
    if X-a in C:
        if X-a!=a:
            cnt += C[X-a]
        else:
            cnt += C[a]
print(cnt)