#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
int main() {
    int n;
    cin >> n;

    vector<int> v(n);
    vector<int> time(n);
    for (int i = 0; i < n; i++) {
        cin >> v[i];
        time[i] = max(1000 - v[i], 1);
    }

    int all_time = 0, pos = 0;
    for (int i = 0; ; i++) {
        int ind = 0;
        for (int j = 0; j < n; j++)
            if (time[j] < time[ind])
                ind = j;

        int res = abs(ind - pos);
        if (res > time[ind]) {
            all_time += time[ind];
            break;
        }
        v[ind]++;


        for (int j = 0; j < n; j++) {
            if (j == ind)
                continue;
            time[j] -= time[ind];
            if (time[j] < 0) {
                break;
            }
        }

        all_time += time[ind];
        time[ind] = max(1000 - v[ind], 1);
        pos = ind;
    }

    cout << all_time;

    // system("pause");
}