/* -*- coding: utf-8 -*-
 *
 * 1664.cc:  No.1664 Unstable f(n) - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const long long LINF = 1LL << 62;

/* typedef */

typedef long long ll;

/* global variables */

/* subroutines */

/* main */

int main() {
  ll n;
  scanf("%lld", &n);

  if (n == 1) puts("1");
  else {
    ll minsum = n; // j = 0 -> 1 + k = n

    for (int i = 2;; i++) {
      int j = 0;
      ll p = 1;
      for (ll m = n; m >= i; j++, m /= i, p *= i);
      ll sum = i + j + (n - p);
      minsum = min(minsum, sum);
      if (j <= 2) break;
    }

    int i0 = 1, i1 = 1000000000 + 1;;
    while (i0 + 1 < i1) {
      int i = (i0 + i1) / 2;
      if ((ll)i * i <= n) i0 = i;
      else i1 = i;
    }
    ll k = n - (ll)i0 * i0;
    minsum = min(minsum, i0 + 2 + k);

    printf("%lld\n", minsum);
  }
  return 0;
}