#include <bits/stdc++.h>
using namespace std;
using lint = long long;
int main() {
  // 遅くても2*10^5分で終わる
  int n, m, t;
  cin >> n >> m >> t;
  vector<int> a(m);
  for (int i = 0; i < m; i++) cin >> a[i], a[i]--;
  vector<int> cnt(n, 0);
  for (int i = 0; i < m; i++) cnt[a[i]]++;
  int high = 0;
  for (int i = 0; i < n; i++) high = max(high, cnt[i]);
  vector<int> cnt2(m+1, 0);
  for (int i = 0; i < n; i++) cnt2[cnt[i]]++;
  for (int i = 0; ; i++) {
    int sum = 0;  // 空いてるやつ
    for (int j = i; j >= 0; j-=t) sum += cnt2[j];
    if (high-sum > t+i) high = high-sum;
    else break;
  }
  cout << high << endl;
}