// Slower C++ solution:
#include <stdio.h>  

#include <algorithm>  

#include <assert.h>

#include <bitset>

#include <cmath>  

#include <complex>  

#include <deque>  

#include <functional>  

#include <iostream>  

#include <limits.h>  

#include <map>  

#include <math.h>  

#include <queue>  

#include <deque>

#include <set>  

#include <stdlib.h>  

#include <string.h>  

#include <string>  

#include <time.h>  

#include <unordered_map>  

#include <unordered_set>  

#include <vector>  

#include <chrono>

#include <random>

#include <time.h>

#include <fstream>

#define ll long long

#define rep2(i,a,b) for(ll i=a;i<=b;++i)

#define rep(i,n) for(ll i=0;i<n;i++)

#define rep3(i,a,b) for(ll i=a;i>=b;i--)

#define pii pair<int,int>

#define pll pair<ll,ll>

#define pq priority_queue<int>

#define pqg priority_queue<int,vector<int>,greater<int>>

#define pb push_back

#define vec vector<int>

#define vecll vector<ll>

#define vecpii vector<pii>

#define endl "\n"

#define all(c) begin(c),end(c)

using namespace std;

int in() {int x;scanf("%d",&x);return x;}

ll lin() {ll x;scanf("%lld",&x);return x;}

void print(vec v){for(auto e:v)cout<<e<<" ";cout<<endl;}

void print(vecll v){for(auto e:v)cout<<e<<" ";cout<<endl;}

void print(map<int,int> mp){for(auto e:mp)cout<<e.first<<" "<<e.second<<endl;cout<<endl;}





#define INF 1e9+7

#define LLINF 1e18+7



ll MOD=998244353;

const int N=160000;



template <ll Modulus> class modint {

  using u64 = ll;



public:

  u64 a;



  constexpr modint(const u64 x = 0) noexcept : a((x%Modulus+Modulus) % Modulus) {}

  constexpr u64 &value() noexcept { return a; }

  constexpr const u64 &value() const noexcept { return a; }

  constexpr modint operator+(const modint rhs) const noexcept {

    return modint(*this) += rhs;

  }

  constexpr modint operator-(const modint rhs) const noexcept {

    return modint(*this) -= rhs;

  }

  constexpr modint operator*(const modint rhs) const noexcept {

    return modint(*this) *= rhs;

  }

  constexpr modint operator/(const modint rhs) const noexcept {

    return modint(*this) /= rhs;

  }

  constexpr modint &operator+=(const modint rhs) noexcept {

    a += rhs.a;

    if (a >= Modulus) {

      a -= Modulus;

    }

    return *this;

  }

  constexpr modint &operator-=(const modint rhs) noexcept {

    if (a < rhs.a) {

      a += Modulus;

    }

    a -= rhs.a;

    return *this;

  }

  constexpr modint &operator*=(const modint rhs) noexcept {

    a = a * rhs.a % Modulus;

    return *this;

  }

  constexpr modint &operator/=(modint rhs) noexcept {

    u64 exp = Modulus - 2;

    while (exp) {

      if (exp % 2) {

        *this *= rhs;

      }

      rhs *= rhs;

      exp /= 2;

    }

    return *this;

  }

};



#define mint modint<998244353>

mint inv[N],comb[N],prd[N],invprd[N];

void calc_inv(){

    inv[1]=1;

    rep2(i,2,N-1){

        inv[i]=inv[MOD%i]*(-MOD/i);

    }

    return;

}

void calc_product(){

    prd[0]=prd[1]=1;

    invprd[0]=invprd[1]=1;

    rep2(i,2,N-1){

        prd[i]=prd[i-1]*i;

        invprd[i]=inv[i]*invprd[i-1];

    }

    return ;

}

void calc_mod(){calc_inv(),calc_product();}

mint cmb(int a,int b){

    if(a<b)return 0;

    if(a<0||b<0)return 0;

    return {prd[a]*invprd[b]*invprd[a-b]};

}

mint modpow(mint x,ll n){

    if(n==0) return 1;

    mint res=modpow(x*x,n/2);

    if(n&1) res=res*x;

    return res;

}



vector<vec> G;

vector<mint> subtree;

mint calc_sub(int x,int p){

    mint res=1;

    for(auto e:G[x]){

        if(e!=p)

        res+=calc_sub(e,x);

    }

    return subtree[x]=res; 

}

struct querry{

    int l,r;

    mint p;

};

int n;

vector<vector<querry>> mem;

vec ls,rs;

void dfs(int x,int p,int &idx){

    ls[x]=idx++;

    vecpii visit;

    for(auto e:G[x]){

        if(e!=p) visit.pb({subtree[e].a,e});

    }

    sort(all(visit));

    for(auto e:visit){

        dfs(e.second,x,idx);

    }

    int now=0,start=0;

    now=subtree[x].a;

    mem[x].pb(querry{0,ls[x],inv[n]*(now)});

    mem[x].pb(querry{ls[x],ls[x]+1,(mint)1});

    rep(i,visit.size()){

        now=visit[i].first,start=ls[visit[i].second];

        while(i<visit.size()-1&&visit[i+1].first==now)i++;

        mem[x].pb(querry{start,rs[visit[i].second],inv[n]*(n-now)});

    }

    rs[x]=idx;

    now=subtree[x].a;

    mem[x].pb(querry{rs[x],n,inv[n]*(now)});

    reverse(all(mem[x]));

    return;

}

template<typename T>

struct BIT{

    vector<T> data;



    BIT(int size){

        data.assign(++size,0);

    }

    T sum(int k){

        T ret=0;

        for(++k;k>0;k-=k&-k) ret+=data[k];

        return (ret);

    }

    void add(int k,T x){

        for(++k;k<data.size();k+=k&-k)data[k]+=x;

    }

};

BIT<mint> bit0(N),bit1(N);

main(){

    ll n=lin();

    ll ans=1e18;

    int sq=sqrt(n);

    for(ll i=sq;i>=1;i--){

        if(n%i==0){

            printf("%lld",n/i+i-2);

            return 0;

        }

    }

}

// Faster C++ solution for the same problem (measured speedup: 3.523807182486573x):
#include <stdio.h>  

#include <algorithm>  

#include <assert.h>

#include <bitset>

#include <cmath>  

#include <complex>  

#include <deque>  

#include <functional>  

#include <iostream>  

#include <limits.h>  

#include <map>  

#include <math.h>  

#include <queue>  

#include <deque>

#include <set>  

#include <stdlib.h>  

#include <string.h>  

#include <string>  

#include <time.h>  

#include <unordered_map>  

#include <unordered_set>  

#include <vector>  

#include <chrono>

#include <random>

#include <time.h>

#include <fstream>

#define ll long long

#define rep2(i,a,b) for(ll i=a;i<=b;++i)

#define rep(i,n) for(ll i=0;i<n;i++)

#define rep3(i,a,b) for(ll i=a;i>=b;i--)

#define pii pair<int,int>

#define pll pair<ll,ll>

#define pq priority_queue<int>

#define pqg priority_queue<int,vector<int>,greater<int>>

#define pb push_back

#define vec vector<int>

#define vecll vector<ll>

#define vecpii vector<pii>

#define endl "\n"

#define all(c) begin(c),end(c)

using namespace std;

int in() {int x;scanf("%d",&x);return x;}

ll lin() {ll x;scanf("%lld",&x);return x;}

void print(vec v){for(auto e:v)cout<<e<<" ";cout<<endl;}

void print(vecll v){for(auto e:v)cout<<e<<" ";cout<<endl;}

void print(map<int,int> mp){for(auto e:mp)cout<<e.first<<" "<<e.second<<endl;cout<<endl;}





#define INF 1e9+7

#define LLINF 1e18+7



main(){

    ll n=lin();

    ll ans=1e18;

    int sq=sqrt(n);

    for(ll i=sq;i>=1;i--){

        if(n%i==0){

            printf("%lld",n/i+i-2);

            return 0;

        }

    }

}