from bisect import bisect_left, bisect_right


def main():
    N, M = map(int, input().split())
    A = sorted(map(int, input().split()))
    if M % 2 == 1:
        print(0)
        return

    triangles = 0
    for a_elm in A:
        if a_elm * 2 > M:
            break
        opposite = a_elm + M // 2
        idx_1 = bisect_left(A, opposite)
        idx_2 = bisect_right(A, opposite)
        if idx_1 < idx_2:
            triangles += N - 2

    print(triangles)


if __name__ == "__main__":
    main()