#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using ll=long long;
using Graph=vector<vector<pair<int,int>>>;
#define MAX 100000
#define MOD 1000000007
#define INF 1000000000000000000

int main(){
  ll n;
  cin>>n;
  ll ans=n+1;
  for(ll i=2;i<=1000000;i++){
    ll x=1;
    int j=0;
    while(x<=n/i){
      x*=i;
      j++;
      ans=min<ll>(ans,i+(ll)j+n-x);
    }
  }
  ll left=0;
  ll right=1000000001;
  while(left+1<right){
    ll x=(left+right)/2;
    if(x*x<=n){
      left=x;
    }else{
      right=x;
    }
  }
  ans=min<ll>(ans,left+2+n-left*left);
  cout<<ans<<'\n';
}