/*
TASK:minitime
LANG:C++
*/
#include<iostream>
#include<string>
using namespace std;
int main()
{int a,b,c=110,i,v,t;
cin>>a;
if(a<=5)c=a;
if(a>5)
{for(i=1;i<=a;i++)
{if(a%i==0)t=a/i;
else t=a/i+1;
v=t+i;
if(v<c)c=v;
}}
cout<<c<<endl; 
}
