/*
TASK:minitime
LANG:C++
*/
#include<iostream>
using namespace std;
int main ()
{
    int n,i,time,min;
    cin>>n;min=n;
    for(i=1;i<=n;i++)
    {
        if(i>1)time=i+(n-(n/i));
        else time=n;
        if(time<=min)min=time;
    }
    cout<<min<<endl;
    return 0;
}    
        
