def calc(X, A):
    B = [0] * (max(A) + 1)
    for ia in A:
        B[ia] += 1
    c = 0
    for i1 in A:
        c += B[X - i1]
    return c


if __name__ == '__main__':
    N, X = map(int, input().split())
    a = list(map(int, input().split()))
    print(calc(X, a))