#include <algorithm>
#include <cstdio>

using std::sort;

#define N 10000

int w[N];

int main() {
  int n, W;
  scanf("%d %d", &n, &W);
  for (int i = 0; i < n; i++) scanf("%d", &w[i]);
  sort(w, w + n);
  int l = 0, r = n - 1;
  int cnt = 0;
  while (l <= r) {
    if (w[l] + w[r] <= W) {
      l++;
    }
    r--;
    cnt++;
  }
  printf("%d\n", cnt);
  return 0;
}