байдарочный поход

n, d = map(int, input().split())
a = sorted(list(map(int, input().split())))
l = 0
r = n-1
answ = 0
while l <= r:
    if a[l] + a[r] <= d:
        answ += 1
        r -= 1
        l += 1
    else:
        r -= 1
        answ += 1
print(answ)