#include <iostream>
#include <set>
#include <algorithm>
using namespace std;

int main()
{

    int n, k;
    cin >> n >> k;

    int a[n];
    for(int i = 0; i < n; i++) {
        cin >> a[i];
    }

    sort(a, a + n);
    int i = 0;
    int j = n - 1;

    int res = 0;
    while(i <= j) {
        if(a[i] + a[j] <= k) {
            i++;
            j--;
        }
        else {
            j--;
        }
        res++;
    }

    cout << res << endl;

    return 0;
}