#include <bits/stdc++.h>
using namespace std;

#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
template <typename T> using min_heap = priority_queue<T, vector<T>, greater<T>>;

#define int long long

signed main() {
	ios::sync_with_stdio(0); cin.tie(0);

	int n, w; cin >> n >> w;
	vector<int> a(13);
	for (int i = 0; i < n; i++) {
		int x; cin >> x; a[x-1]++;
	}

	vector<int> dp(1 << 13, 998244353);
	dp[0] = 0;
	for (int i = 0; i < (1 << 13); i++) {
		int m = ((1 << 13) - 1) ^ i;
		for (int x = m; x; ) { 
			// try submask x
			int sm = 0;
			for (int j = 0; j < 13; j++) {
				if (x & (1 << j)) sm += a[j];
			}
			if (sm <= w) {
				dp[i^x] = min(dp[i^x], dp[i] + 1);
			}

			--x &= m;
		}
	}
	cout << dp[(1 << 13) - 1] << '\n';

	return 0;
}