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
57
58
59
60
61
62
63
64
65
66
67
68
// Daniel Grzegorzewski
// while (clock()<=69*CLOCKS_PER_SEC)
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
// #pragma GCC optimize("Ofast")
// #pragma GCC target("avx,avx2,fma")

#define MP make_pair
#define PB push_back
#define ST first
#define ND second

using namespace __gnu_pbds;
using namespace std;

template <typename T>
using ordered_set =
    tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

//X.find_by_order(k); - zwraca iterator na k-ty element (numeracja od zerowego)
//X.order_of_key(k); - zwraca liczbę elementów ostro mniejszych niż k

typedef pair<int, int> PII;
typedef vector<int> VI;
typedef vector<PII> VII;
typedef long long LL;

void init_ios() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
}

const uint64_t SEED = chrono::steady_clock::now().time_since_epoch().count();
mt19937_64 rng(SEED);

const int N = 5*(int)1e5 + 3;

int n, res;
map<int, int> m;
multiset<int> s;

int main() {
  init_ios();
  cin >> n;
  for (int i = 1; i <= n; ++i) {
    int x;
    cin >> x;
    m[x]++;
  }
  for (auto it: m)
    s.insert(it.ND);
  while (!s.empty()) {
    ++res;
    auto it = --s.end();
    int toRem = (*it)-1;
    s.erase(it);
    while (toRem > 0 && !s.empty()) {
      auto it2 = s.begin();
      int val = *it2;
      s.erase(it2);
      if (toRem < val)
        s.insert(val-toRem);
      toRem -= val;
    }
  }
  cout<<res<<"\n";
}