#include <bits/stdc++.h>

#define x first
#define y second
#define el '\n'
#define debug(x) cout << #x << ": " << x << el
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const int N = 3e5 + 10, INF = 0x3f3f3f3f, mod = 998244353;

void inc(ll &a, ll b) {
    a += b;
    if (a >= mod) a -= mod;
}

void dec(ll &a, ll b) {
    a -= b;
    if (a < 0) a += mod;
}

ll add(ll a, ll b) {
    a += b;
    return a >= mod ? a - mod : a;
}

ll del(ll a, ll b) {
    a -= b;
    return a < 0 ? a + mod : a;
}

int 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> v(1 << 13);
    vector<vector<int>> nums(14);
    vector<int> f(1 << 13, 13);
    f[0] = 0;
    for (int i = 0; i < 1 << 13; ++i) {
        nums[__builtin_popcount(i)].emplace_back(i);
        for (int j = 0; j < 13; ++j) {
            if (i >> j & 1) v[i] += a[j];
        }
        if (v[i] <= W) f[i] = 1;
    }
    for (int i = 1; i <= 13; ++i) {
        for (int j: nums[i]) {
            for (int k = 0; k < 1 << 13; ++k) {
                f[j | k] = min(f[j | k], f[j] + f[k]);
            }
        }
    }
    cout << f[(1 << 13) - 1] << el;
}