#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vll = vector<ll>;
using vvll = vector<vll>;
using vvvll = vector<vvll>;
using vb = vector<bool>;
#define all(A) A.begin(),A.end()
#define rep(i, n) for (ll i = 0; i < (ll) (n); i++)
template<class T>
bool chmax(T& p, T q, bool C = 1) {
    if (C == 0 && p == q) {
        return 1;
    }
    if (p < q) {
        p = q;
        return 1;
    }
    else {
        return 0;
    }
}
template<class T>
bool chmin(T& p, T q, bool C = 1) {
    if (C == 0 && p == q) {
        return 1;
    }
    if (p > q) {
        p = q;
        return 1;
    }
    else {
        return 0;
    }
}
ll modPow(long long a, long long n, long long p) {
    if (n == 0) return 1; // 0乗にも対応する場合
    if (n == 1) return a % p;
    if (n % 2 == 1) return (a * modPow(a, n - 1, p)) % p;
    long long t = modPow(a, n / 2, p);
    return (t * t) % p;
}
ll gcd(ll(a), ll(b)) {
    if (a == 0)return b;
    if (b == 0)return a;
    ll c = a;
    while (a % b != 0) {
        c = a % b;
        a = b;
        b = c;
    }
    return b;
}
ll sqrtz(ll N) {
    ll L = 0;
    ll R = sqrt(N) + 10000;
    while (abs(R - L) > 1) {
        ll mid = (R + L) / 2;
        if (mid * mid <= N)L = mid;
        else R = mid;
    }
    return L;
}

bool DEB = 0;

int main() {

    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    ll N,W;
    cin>>N>>W;
    vll A(13,0);
    rep(i,N){
        ll a;
        cin>>a;
        A[a-1]++;
    }
    vll DP(1<<13,1e18);
    DP[0]=0;
    rep(bit,(1<<13)){
        for (ll b = bit; b >= 0; b = (b - 1) & bit) {
            ll pl=0;
            rep(j,13){
                if(b&(1<<j)){
                    pl+=A[j];
                }
            }
            if(pl<=W){
                chmin(DP[bit],DP[bit-b]+1);
            }
            if (b == 0)break;
        }
    }
    cout<<DP[(1<<13)-1]<<endl;
}