#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int main()
{
    int n;
    cin >> n;

    vector<int> husik(n);

    for(int i = 0; i < n; i++) {
        cin >> husik[i];
    }

    sort(husik.rbegin(), husik.rend());

    int maximum = 0;
    for(int i = 0; i < n; i++) {
        if(maximum < husik[i] + i) {
            maximum = husik[i] + i;
        }
    }

    cout << maximum;

    return 0;
}