//  Created by Никита on 11.10.17.
//  Copyright © 2017 Никита. All rights reserved.
//

#include <iostream>
    using namespace std;
    int main(int argc, const char * argv[])
{
        int i, n, x;
        int a[100000];
        x = 0;
        cin >> n;

        for (i=0; i<n; i++)
        {
            cin >> a[i];
        }
        i=n-1;
        int r=n-1;
    while (i>0)
    {
        while (i > 0 && a[n-1]==a[i-1]) {r--; i--;};
        if ((x + (n - r)) > a[n-1] - 1) break;
        x+=n-r;
        a[n-1]--;
    }
        if (i==0)
            cout << (x+a[n-1]*n + n)/(n+1);
        else if (a[n-1]>x)
            cout << a[n-1];
        else
            cout << x;

    return 0;

}