#include <iostream>
#include <stdio.h>
#include <cstring>
#include <algorithm>
using namespace std;
#define LL long long
LL n, m, ans;
LL w[10010];


int main()
{
    //freopen("1.txt", "r", stdin);
    cin >> n >> m;
    for (int i = 0; i < n; i++)
        cin >> w[i];

    sort(w, w+n);
    int L = 0, R = n-1;
    while (L <= R) {
        if (w[L] + w[R] <= m)
            L++;
        R--;
        ans++;
    }
    cout << ans;

    return 0;
}