1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
#include <bits/stdc++.h>
#ifdef dbg
#define D(...) fprintf(stderr, __VA_ARGS__)
#define DD(...) D("[Debug] "#__VA_ARGS__ " = "), \
              debug_helper::debug(__VA_ARGS__), D("\n")
#include "C:\Users\wsyear\Desktop\OI\templates\debug.hpp"
#else
#define D(...) ((void)0)
#define DD(...) ((void)0)
#endif
#define rep(i, j, k) for (int i = (j); i <= (k); ++i)
#define per(i, j, k) for (int i = (j); i >= (k); --i)
#define SZ(v) int((v).size())
#define ALL(v) (v).begin(),(v).end()
#define fi first
#define se second
using ll = long long;
using pii = std::pair<int, int>;
using pll = std::pair<ll, ll>;

template<class T> void chkmn(T &x, T y) { if (y < x) x = y; }
template<class T> void chkmx(T &x, T y) { if (y > x) x = y; }

using namespace std;

const int maxn = 500010;

int n, a[maxn], cnt[maxn];

int main() {
  cin.tie(nullptr) -> ios::sync_with_stdio(false);
  cin >> n;
  rep (i, 1, n) cin >> a[i], cnt[a[i]]++;
  sort(cnt + 1, cnt + n + 1);
  reverse(cnt + 1, cnt + n + 1);
  int tot = n, ans = 0;
  while (!cnt[tot]) tot--;
  int pos = 1;
  while (pos <= tot) {
    while (!cnt[tot]) tot--;
    if (pos > tot) break;
    ans++;
    if (pos == tot) break;
    int lim = cnt[pos++] - 1;
    while (tot >= pos) {
      if (cnt[tot] <= lim) {
        lim -= cnt[tot];
        cnt[tot--] = 0;
      } else {
        cnt[tot] -= lim;
        break;
      }
    }
  }
  cout << ans << '\n';
}