#include "bits/stdc++.h"
#ifdef LOCAL
#include "bits/debug.h"
#else
#define dd(...) 42
#endif
#define ll long long
#define ull unsigned long long
#define nl '\n'
#define all(a) begin(a), end(a)
#define rall(a) rbegin(a) rend(a)
#define sz(a) ((int)a.size())
#define ff first
#define ss second
#define f(i, n) for (int i = 0; i < n; ++i)
// #define PROB_NAME "sliding"
using namespace std;
// const int INF = 1e9;
// const ll INFF = 1e18;
// const int M = 1e9 + 7;
ll d, h, n, m, k, p, q, x, y, z;
bool pos(vector<ll>& cnt, ll M) {
// day i has cnt[i] tasks
// M tasks can be done per day
// keep feeding tasks to the machine, count days
ll days = 0;
ll older_tasks = 0;
for (ll i = 1; i <= n; ++i) {
days += (older_tasks + cnt[i]) / M;
older_tasks = cnt[i] % M;
}
return days <= n + d;
}
void solve() {
cin >> n >> d >> m;
vector<ll> cnt(n + 1, 0);
vector<ll> a;
f(i, m) {
cin >> x;
a.push_back(x);
}
f(i, m) { ++cnt[a[i]]; }
ll L = 1, R = 1e9;
ll ans = R;
while (L <= R) {
ll M = L + (R - L) / 2;
if (pos(cnt, M)) {
ans = min(ans, M);
R = M - 1;
} else {
L = M + 1;
}
}
assert(ans != 1e9);
cout << ans << nl;
}
void TESTCASES() {
int t = 1;
// cin >> t;
for (int i = 1; i <= t; ++i) {
solve();
}
}
int32_t main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
#ifdef PROB_NAME
freopen(PROB_NAME ".in", "r", stdin);
freopen(PROB_NAME ".out", "w", stdout);
#endif
TESTCASES();
}
