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
#include <bits/stdc++.h>
#define dbg(x) " [" << #x << ": " << (x) << "] "
using namespace std;
using ll = long long;
template<typename A, typename B>
ostream& operator<<(ostream& out, const pair<A,B>& p) {
    return out << "(" << p.first << ", " << p.second << ")";
}
template<typename T>
ostream& operator<<(ostream& out, const vector<T>& c) {
    out << "{";
    for(auto it = c.begin(); it != c.end(); it++) {
        if(it != c.begin()) out << ", ";
        out << *it;
    }
    return out << "}";
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    int n;
    cin >> n;
    vector<int> v(n), cnt(n + 1);
    for(int& i : v) {
        cin >> i;
        cnt[i]++;
    }

    set<pair<int, int>> st;
    for(int i = 1; i <= n; i++) {
        if(cnt[i]) {
            st.insert({cnt[i], i});
        }
    }

    int ans = 0;
    while(!st.empty()) {
        auto it = --st.end();
        auto [len, i] = *it;
        st.erase(it);
        ans++;
        if(st.empty()) break;
        int mx_len = 2 * len - 1;
        while(!st.empty()) {
            auto [x, i] = *st.begin();
            st.erase(st.begin());
            if(len + x <= mx_len) {
                len += x;
            } else {
                int add = mx_len - len;
                len += add;
                cnt[i] -= add;
                st.insert({cnt[i], i});
                break;
            }
        }
    }
    cout << ans << endl;

    return 0;
}