using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var n = long.Parse(ReadLine());
        var ans = n + 1;
        for (var i = 2; i <= ans; ++i)
        {
            var j = 0;
            var ij = 1L;
            var tmp = n;
            while (tmp >= i)
            {
                ++j;
                ij *= i;
                tmp /= i;
            }
            // WriteLine($"{i} {j} {ij} {tmp}");
            ans = Math.Min(ans, i + j + n - ij);
        }
        WriteLine(ans);
    }
}