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#include <bits/stdc++.h>
#include <cstdint>

using std::cin, std::cout;
using std::string;
using std::array;
using std::vector;
using i8 = int8_t;
using u8 = uint8_t;
using i16 = int16_t;
using u16 = uint16_t;
using i32 = int32_t;
using u32 = uint32_t;
using i64 = int64_t;
using u64 = uint64_t;
const char endl = '\n';

template<class num>
inline num ceildiv(num a, num b) { return (a + b - 1) / b; }

template<class num>
inline num modulo(num i, num n) { //return value >= 0
    const num k = i % n;
    return k < 0 ? k + n : k;
}

const int max_n = 500000 + 5;

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

    int occurences[max_n]{};
    
    int n;
    cin >> n;

    for (int i = 0; i < n; i++) {
        int input;
        cin >> input;

        occurences[input]++;
    }

    vector<int> occurence_count; // all non-zero elements of occurences[]

    for (int count : occurences) {
        if (count != 0) occurence_count.push_back(count);
    }

    std::ranges::sort(occurence_count);

    {
        int n = occurence_count.size();

        int sets = 0;
        int left = -1;
        int right = n;
        int space = 0;

        while (left + 1 < right) {
            if (space > 0) {
                left++;
                space -= occurence_count[left];
            } else {
                sets++;

                right--;
                space += occurence_count[right] - 1;
            }
        }

        if (space < 0) sets++;

        // int set = 0;
        // int space = 0;
        // for (int i = 0; i < n - set; i++) {
        //     space -= occurence_count[i];

        //     while (space < 0) {
        //         set++;
        //         space += occurence_count[n - set] - 1;
                
        //         if (i >= n - set) {
        //             space = INT_MAX; // we already made space for o[i] by making a set for it
        //             break;
        //         }
        //     }
        // }

        cout << sets;
    }
    cout << endl;
    return 0;
}